Hot Take: Mike was that good at his job.
What about it?
Failed cop.
Failed his niece by living a private life, putting her in jeopardy.
Failed the German engineer by not teaching him a hard enough lesson first, then by letting him escape, and then by killing him.
Failed Nacho (and his dad), first via involvement, then by organizing the failed assault in Lalo's compound, finally with Nacho having to kill himself.
Failed Saul and Kim by letting Howard get murdered because he was simultaneously not handling the Lalo situation properly
Failed Gus, boom boom.