There is an evaluation process, I might add this is 8 or 9 years ago I knew an NFL official.
They are graded after every game for penalties they called and whether they were accurate, whether they missed a play they shouldn’t have or judgement calls that they should or shouldn’t call.
For an example he showed me a play that his crew threw a flag on that was a legit holding penalty by a WR but it was away from the play. I believe it was a run play to the left and a WR on the right was holding. The ref ended up getting docked because the NFL said he shouldn’t have thrown it because it didn’t directly affect the play