Very, very few pilots get terminated on probation here. It would have to be flagrant, repeated violations or the usual lie/cheat/steal that could get anyone terminated. Once off IOE, probies basically have the same protections as a non probationary pilot. Only difference is ALPA can't file a disciplinary grievance.

The place to weed them out is the interview or indoc/initial training when they can be fired for any reason.

The 9E flows actually seem to have most of the attitude problems. There's a whole lot of them that stayed for the flow because they couldn't get hired anywhere else, for clear reasons. They come to training and act like they're doing us a favor by being here.