Board Thread:Improvements and Issues/@comment-6342763-20130615122051/@comment-11139670-20130621231121

In fact thinking about this a little more it is actually much more difficult for a soul to become a shinigami than it is for a soul to become a hollow. The reasoning being that only souls with a much higher spirit energy are capable of training and joining the shinigami (i.e. most souls in soul society are incapable of training to become shinigami because they don't posses the spirit energy of an average shinigami). Whereas any soul that doesn't go to soul society and remains in the human world will eventual turn into a hollow regardless of there spirit energy level. Hence shinigami are in some ways unique souls compared to mere ordinary low energy souls (though I will admit that amongst high energy souls there is nothing unique about becoming a shinigami since it just a matter of training.)