On the difficulty of computing the truck factor

In spite of the potential relevance for managers and even though the Truck Factor definition is well-known in the "agile world" for many years, shared and validated measurements, algorithms, tools, thresholds and empirical studies on this topic are still lacking. In this paper, we explore the situation implementing the only approach proposed in literature able to compute the Truck Factor. Then, using our tool, we conduct an exploratory study with 37 open source projects for discovering limitations and drawbacks that could prevent its usage. Lessons learnt from the execution of the exploratory study and open issues are drawn at the end of this work. The most important lesson that we have learnt is that more research is needed to render the notion of Truck Factor operative and usable. © 2011 Springer-Verlag.