The feat Leadership has changed considerably since 3.X days and has brought up a few debates at my table.
The specific debate is not over cohorts, but over followers. Let's say my level 7 Pathfinder Cleric has a leadership score of 12, this means he gains a cohort of level 5 and 8 level 1 followers with a PC class. If my Cleric were to arm his followers with weapons, take them into battle, and they all died, would he be able to gain more followers (after figuring in the -1 to his score for having followers killed under him)?
So, my question is this: If your followers die, are you able to gain more, or do you have to wait until either you level or your leadership score increases?