The causes of failure of ERP projects are widely recognized and have been the subject of numerous publications. This paper aims to detect new weaknesses explaining frequent drifts in skills management in these projects. It is a question of better understanding the dysfunctions of the current mechanisms of management and of studying their impact on the performance of the projects. A few studies have looked at phenomena that cause cycle breaks and which are the source of instabilities in the skills management causing additional delays and costs. From this conceptual representation based on Forrester’s dynamics system, we developed a simulation model for this dynamic behaviors study.