Our previously presented model of abdominal aneurysm formation allowed to simulate aneurysm dynamics relying on a postulated initial wall failure without being able to predict the actual location of such weakening. In this study we investigate what factors can trigger pathology progression at positions eventually observed in reality. We consider mechanical effects inside the arterial wall and their possible contributions to the formation of an aneurysm. Using a computer model we demonstrate the existence of wall regions susceptible to failure due to increased oscillatory mechanical loading. We find these regions to be uniquely correlated with actually observed aneurysm locations. We demonstrate that wall fatigue and failure are probable factors influencing the formation of an abdominal aortic aneurysm.