I think you want more than that from a coach but you just worded that statement a little misleadingly.I don’t think you fire him based on this year or two years ago. You fire him based on what you think he is going to do next year.
What Pitino may do next year shouldn't be enough to save him.
Let's assume for the moment that this season concludes as expected at this point: a record below .500 overall and well below .500 in the conference. If that is the result, that will mean that Pitino has failed to achieve two consecutive good years during his 7 year tenure.
Perhaps, if things go right and there are no significant departures, Pitino may have a good team next year. What about the year after? Do we trust this coach to field teams who are capable of being even modestly successful over two consecutive years?
Good (or even decent) programs should be able to field teams that are at least moderately successful over a two or three year period. I don't see any reason to trust this coach to do that.