INTJ as a leader

Is it true that INTJs don't naturally spring to leadership unless the situation absolutely necessitates it and they do it a last resort thing? This concept always baffled me because I'm the kind of person who assumes leadership roles whenever the opportunity presents itself and especially when I feel that the role is in line with my natural abilities and skills. My question to you guys is: As an INTJ, where do you usually stand in the leadership ladder and what is your thought process as to why you opt to be at that step of the ladder and not another one?