http://www.nytimes.com/2014/06/27/wo...-370.html?_r=0
Advocates of the hypoxia theory argue that pilot suicide cases tend to involve pilots who crashed their planes suddenly, not after hours of flight. A clinical psychologist advising the investigation has been very skeptical of the suicide theory, saying it would be highly unusual for a suicidal person to proceed with such a deadly plan over many hours, investigators said.
If Zahari's aim was to hide the plane forever, to punish the Malaysian government or whatever, he might have seen the prospect of his own death as collateral damage. During times of war, men sometimes do things even when their death is inevitable; we regard them as brave warriors. One clinical psychologist talking about his experience of typical suicidal patients is irrelevant, there is nothing "usual" about this case - it is weird, whatever the "final" explanation is presented to us.