The criteria is essentially ‘you meet these criteria AND it causes clear problems with your ability to live your life’.
It doesn’t mean you have a bad job and X, therefore you have ADHD. Rather, you show ADHD traits and they get in the way (and cause you distress) in doing a job you otherwise would be entirely capable of doing. Or consistently fail (and have distress) on social environments you’d otherwise be perfectly fine in, etc.
If you don’t have a criteria like that, there is no useful criteria at all, since practically all medicine is oriented towards fixing things that aren’t working correctly/causing problems.
It’s the same type of criteria used for evaluating everything from heart disease to stroke to a broken bone. Or in other words ‘if it ain’t broken, then it isn’t broken.’