​​Leader derailment, characterized by the stagnation, demotion, or termination of leaders' careers, is an increasingly alarming triangular issue. This phenomenon not only disrupts individual career trajectories but also poses significant challenges for organizational stability and effectiveness. Various factors, both internal and external to the leader, can trigger leader derailment, a complex problem that causes a career crisis. This qualitative study, recognizing the invaluable insights of certified and trained executive coaches, sought their expertise to understand why many leaders derail rather than succeed. Although scholars have studied the monographs on leader derailment, they have yet to delve into executive coaches' perspectives to understand their perceptions of the internal and external factors contributing to derailment. This research covered that gap and was both exploratory and confirmatory. It was confirmatory because it validated existing research on leader derailment, whereas it was exploratory because it probed and uncovered new theoretical territory and provided novel insights. The primary research question that guided this study was: What do executive coaches perceive as the major internal and external factors derailing leaders? The analysis of this study’s data revealed specific recurring reasons, such as: (a) inadequate emotional intelligence; (b) dysfunctional personality; (c) poor polarity management; and (d) organizational landmines. Consequently, this study's results did not contradict existing research, but rather added to it by showing that leader derailment is a multilayered problem, with the following findings: (a) emotional intelligence enables better leadership qualities and significantly determines how a leader is perceived; (b) an undiscovered and unregulated personality in a leader can be problematic; (c) it is crucial for leaders to recognize and manage polarities; (d) an organization can become a pitfall for a leader; and (e) office politics is unavoidable and beware of workplace abuse and bullies. However, this research discovered an anomaly—a notable deviation from these findings. Despite the major factors and patterns identified as prone to derailing leaders, some leaders remain immune to them. This study probed into the intricacies and found that a leader's unique brilliance, such as charisma, superior technical ability, innovative-visionary prowess, and a strong team and network, can often lead people to discount and overlook their shortcomings, thereby attributing the leader with high idiosyncrasy credits. This study concludes that several factors, each with its own unique influence, contribute to the complexity and perplexity of leader derailment.