اثرات مدیریت پروژه برنامه محور در محیط های چند پروژه ای

Prior work has affirmed the importance of studying project management in multi-project environments. A challenge in these settings pertains to the need to share skilled resources across concurrent projects when project management is schedule-driven and resource capacity is fully committed. To probe into this problem, we use a system dynamics simulation grounded on in-depth fieldwork with a high-performance truck developer. We simulate the effects of capturing resources allocated originally to one project so as to speed up another product development project that started late. Our central contribution is to illuminate how a schedule-driven project management policy can lead to a vicious cycle that degrades the organization's capability to meet the planned project milestones in the long-term. Whilst capturing resources can ensure that a tardy but ‘business-critical’ project is delivered on time, if the organization has no free resource capacity and is also not recruiting more staff, this practice harms the schedule performance of the projects deprived from resources. Further, the workforce's productivity gradually deteriorates as the frequency with which staff switches back and forth between projects increases. These effects compounded cause delays in all the subsequent projects, irremediably degrading the organization's capability to deliver projects on time reliably.

How do product development and manufacturing firms survive in competitive markets? To survive, seminal studies show that these firms have to keep continuously making incremental improvements to existing products and developing new products that incorporate emergent technologies (Wheelwright and Clark, 1992). New product development therefore typically unfolds in a multi-project environment wherein different teams have to share some skilled and scarce engineering and design resources (Laslo and Goldberg, 2008, Geraldi, 2008 and Canonico and Söderlund, 2010). In competitive markets, manufacturers also tend to operate under pressure to accelerate product development and reduce time to market so as to meet the customers' evolving needs and demand for cutting-edge technologies (Lieberman and Montgomery, 1988, Calantone and Benedetto, 2000 and Ward et al., 1995). In this study, we define schedule pressure as the tension caused by the gap between the project manager's perception of the work days necessary to complete the project with the resources originally allocated to the team and the actual work days left before the planned completion date. Schedule pressure is low if the project appears to be on time and the work left is unlikely to require the team to work long hours. But it is high if the project team perceives planned milestones will be missed unless the project is de-scoped or staff put long hours, even assuming that no unexpected ‘fires’ (Repenning, 2001) emerge in the late stages. Existing studies suggest that projects unfolding in multi-project environments under schedule pressure are frequently delayed, a phenomenon which tends to negatively impact on the firm's overall business performance (Griffin, 1997 and Blichfeldt and Eskerod, 2008). A fundamental insight that emerges from studies of multi-project organizations is that specialized resources switch frequently between projects in these settings, and this is a root cause of schedule pressure (Geraldi, 2008, Kaulio, 2008, Laslo and Goldberg, 2008, Jonas, 2010 and Canonico and Söderlund, 2010). In particular, top management may find it attractive to capture resources from other concurrent projects so as to accelerate a business-critical project that started late if the organization has no free capacity in terms of specialized resources and is not hiring new staff, or the organization is finding it difficult to recruit new staff with adequate skills (Yaghootkar, 2010). In the short-term, the bold practice of capturing resources from a concurrent project can be effective to ensure that the project deemed ‘more important’ finishes on time. However, increasing the size of a project team to attempt to speed up project delivery is notorious for decreasing productivity (Brooks, 1995). Work productivity also deteriorates because learning curves get disrupted as resources switch back and forth between projects (Abdel-Hamid, 1988). These insights leave open, however, the central issue addressed here. Specifically, we ask: ‘which are the long-term effects of schedule-driven project management sustained by a resource capturing practice in a multi-project organization when there is no free resource capacity?’ Our research design is a longitudinal, experiential simulation of a multi-project organization in which a resource capturing practice is used to implement a schedule-driven project management policy. Our computer-simulated environment is grounded on in-depth fieldwork with the product development organization of a manufacturer for high-performance trucks. We assume that, first, there is no free resource capacity; second, skilled staff are not being recruited; and third, productivity declines when resources switch back and forth between concurrent projects. Our simulation includes various scenarios that increase deliberately the initial delay in starting a project deemed ‘business-critical’. Due to the schedule-driven project management policy, these delays increase the frequency with which resources switch between concurrent projects. Our central contribution is to illuminate the short-term logic and long-term detrimental effects of decisions to capture resources allocated to other concurrent projects. In the short-term, this policy ensures that a tardy project can be delivered on time. This can be business-critical, for example, when the business faces the prospect of significant loss of anticipated revenues if the project output fails to reach the market before a pre-determined calendar date or before a competitor reaches the market with a similar product. Ensuring that some projects finish on time can also be business-critical if a contract with a third-party imposes significant penalties for delays. In the long-term, we show that a resource capturing practice in an environment without free capacity puts the concurrent projects under schedule pressure in a ripple effect. Assuming productivity deteriorates as resources move across projects routinely in agreement with existing studies, we show that schedule-driven management with resource capturing exacerbates schedule pressure in a self-reinforcing vicious cycle, generating a persistent steady state that degrades the organization's capability to deliver projects on time reliably.

Our study reveals how a schedule-driven project management policy sustained on capturing resources from concurrent projects can harm the long-term multi-project organization's capability to meet planned project milestones. This insight is grounded in a context in which the organization has no free resource capacity but is nonetheless reluctant to hire new staff, relying instead on the existing workforce to work overtime — a scenario not atypical in jobless economic recoveries (The Economist, 2010). Specifically, the experiments illustrate that as top management puts pressure on a team to complete a particular project on time, the delays in the elapsed durations of subsequent projects added together tend to exponentially increase due to a conflation of factors: first, as one project loses resources, it also becomes under schedule pressure after a time delay; second, as more projects become under schedule pressure, resources switch back and forth more frequently in response to increased oscillation in project priorities; and third, with increased fluctuation in the teams' size, productivity decreases. These effects compounded exacerbate schedule pressure in a self-reinforcing vicious cycle, generating a persistent steady state that degrades the organization's long-term performance in terms of its capability to deliver projects efficiently. This result is consistent with Repenning's (2001) claim that fire-fighting is self-reinforcing. It is also in agreement with prior studies which suggest that the urgency to resolve short-term problems often motivates organizations to overlook the long-term effects of short-term fixes (Repenning, 2001). Interestingly, our fieldwork reveals practitioners are aware that a schedule-driven management policy can harm the long-term organization's capability to deliver projects efficiently. But the empirical findings also suggest that conventional wisdom has been inadequate to talk top management out of deep-seated practice. These insights add to extant scholarly literature on the structure and behavior of multi-project organizations (Repenning, 2001, Geraldi, 2008, Aritua et al., 2009 and Laslo and Goldberg, 2008). Seminal studies have highlighted the negative consequences for a product development firm carrying on more projects than its resources can handle effectively. Metaphorically, Wheelwright and Clark (1992 p. 90) call it the ‘Canary Cage problem’ — canaries (projects) which are weaker find themselves pushed to the bottom of the cage, dumped on by their fellow canaries, and they become sick and die. It was an open issue in the literature, however, the extent to which this problem results exclusively from resource scarcity, or rather, it should be attributed as well to the application of particular project management policies. Based on an in-depth empirical study and experiential simulation, our central contribution is to show how schedule-driven project management when there is no free resource capacity can deteriorate permanently the multi-project organization's capability to deliver projects on time. Importantly, this insight suggests that best practice in single-project management, notably upfront planning and strategizing (Morris, 1994 and Repenning, 2001), can have limited benefits if top management ignores the deleterious long-term effects of ‘hijacking’ systematically resources from concurrent projects. Indeed, our fieldwork indicates a badly implemented schedule-driven project management policy can lead to disenchantment among project staff who, disheartened with (and powerless to change) top management's attitudes have no choice but to get accustomed to reactive but ineffective project management practice. A second contribution is reinvigorating computer-based simulation in project management studies of multi-project organizations. These organizations are complex adaptive systems (Aritua et al., 2009). But despite the suitability of system dynamics to study complex systems (Sterman, 1994 and Sterman, 2000), its use and the use of computer-based simulation more generally is rare in recent literature — Laslo and Goldberg (2008) is the exception. Our combination of in-depth fieldwork and computer-based simulation therefore introduces methodological diversity, and responds to recent calls for in-depth empirical and analytical studies of project performance in multi-project organizations. This study has also important contributions to practice. First, we believe its managerial insights and product outputs may be useful to help persuade multi-project organizations to stop rewarding top management on the basis of their ability to implement short-term fixes regardless of their negative, long-term impacts to the organization's performance. Our results show instead that multi-project organizations need to put in place incentives and rewards that ensure top management keeps a holistic view. Such view can contribute to ensure top management is mindful of the importance of negotiating project budgets and resource allocations within the planned timescales so as to avoid pushing back new projects. To be effective, top and middle management need to be capable to forge consensus, a pre-requisite for high-performing multi-project organizations (Laslo and Goldberg, 2008). And second, our results suggest that top management want to proactively keep some free capacity in regards to specialized resources. Like investments in product flexibility (de Neufville and Scholtes, 2011), organizations ought to frame an investment in free resource capacity as acquiring an insurance against future eventualities. This investment will then pay off whenever a critical project becomes unexpectedly under schedule pressure. Taken together, these insights also suggest firms need to supplement investments in training, processes, and education to improve single-project management with commensurate investments focused on managing multi-project environments. 6.1. Limitations and outlook Like all studies, ours has limitations that open up opportunities for future research. First, the characteristics of the empirical setting informing the simulation model limit the external validity of this study. As a manufacturer of high-performance trucks operating in a competitive market, Alpha is developing constantly new variants and configuration options. Albeit incremental, these projects are undertaken by skilled resources that take time to recruit even when organizations are not reluctant to hire. These conditions are core to Alpha's multi-project nature, and qualify the generalizability of our insights. More studies are needed to falsify their validity into dissimilar multi-project settings. Second, the simulation model also merits further development. Noteworthy, the simulation provides a stylised representation of a multi-project environment. Specifically, it simulates projects as if consisting of only one stage when a thorough analysis of Alpha's stage and gate model (Cooper, 1990) reveals six main stages and seven gates, each stage arguably requiring different resources. The simulation also does not capture the interfaces between Alpha's development division and its numerous product development suppliers, nor technical interdependencies between the project outputs and inputs. It therefore remains indeterminate how inter-firm relationships and technical interdependences between projects affect responses to schedule pressure. Third, we incorporated in the model some analytical assumptions for the sake of tractability which can be relaxed in future studies. For instance, the simulation assumes that when the start of the first project is delayed, its target deadline remains unchanged. We also assume that a tardy project will capture resources from a concurrent project irrespectively of the negative impacts to that project. These assumptions are grounded on fieldwork. Admittedly, however, other organizations can operate under more flexible policies (Canonico and Söderlund, 2010), or can empower project managers to oppose attempts to hijack resources from their teams (Jonas, 2010). Project leadership capabilities can also be essential to pre-empt conflict between top management and middle managers around budgets and resource allocations (Kaulio, 2008 and Laslo and Goldberg, 2008). It thus merits exploring how alternative policies and soft variables impact long-term project scheduling performance in multi-project environments. In conclusion, we should further note that our model assesses project priorities based only on schedule pressure and focuses on how resource capturing affects project scheduling reliability. However, the organization's ability to meet planned project milestones is but one dimension of its overall performance. Arguably, in some instances, the revenue from overcoming an otherwise delay of a business-critical project that started late may offset the delay expenses stemming from disrupting other project deliveries. Organizations may also be able to mitigate the risk of declining work productivity, at least partly, when resources move between projects, a scenario not accounted for in this research. Future studies should therefore build in a set of priority rules and risk mitigation procedures that enable a comprehensive assessment of the trade-offs with implementing a schedule-driven project management policy in multi-project organizations.