Until someone else responds, I just wanted to link a previous thread on the topic of kamikaze pilots (there are also more good posts in that thread if you scroll down).

A very brief summary of the thread I linked is that the military situation was extremely already dire: kamikaze attacks were less of a sustainable military strategy, and rather an act of desperation. There are several good posts in the thread that go over the atmosphere and attitudes of kamikaze pilots at the time in much more detail than I am able to.

Edit: I've searched and found another thread that more closely addresses your original question of pilot "selection."