According to the Dunning-Kruger effect, competent people do not think of themselves as unusually competent. According to a paper by John Mueller and Mark G. Stewart (PDF – 227kb) reviewing terrorism case studies, competent people don’t try to blow themselves and others up either:

In all, as Shikha Dalmia has put it, would-be terrorists need to be “radicalized enough to die for their cause; Westernized enough to move around without raising red flags; ingenious enough to exploit loopholes in the security apparatus; meticulous enough to attend to the myriad logistical details that could torpedo the operation; self-sufficient enough to make all the preparations without enlisting outsiders who might give them away; disciplined enough to maintain complete secrecy; and—above all—psychologically tough enough to keep functioning at a high level without cracking in the face of their own impending death.” The case studies examined in this article certainly do not abound with people with such characteristics.

*Platonic, athletically contextualized, butt slap of gratitude to Cory Doctorow for bringing this to everyone’s attention.