> If you're firing an employee, they should have known (almost as long as you've known) that there was some culture mismatch, or that their performance wasn't meeting expectations, or whatever.

>> there was some culture mismatch, or that their performance wasn't meeting expectations

I had trouble reading this: culture, or performance. If their performance was good, but they didn't match the 'culture' then it is arbitrary in the greatest order. If 'culture; is important, as I agree it is but in qualifiable ways, so culture is qualifiable, and if an organization cannot put 'culture; into its performance expections, it is likely doomed or very very young, but likely doomed.