[Flavious_Maximus]

Why does Trump do things like this?

It was enough to just say “I endorse Kevin McCarthy for another term’. He didn’t have to go so over the top by calling McCarthy “Outstanding”.

Trump hurts the MAGA cause when he praises those milksop Republicans who openly fight against conservatives.

[Dr. Franklin]

Why does Trump do things like this?

Yes, it's Trump's need to tout the success of his endorsements. If McCarthy doesn't have a viable challenger, and the Dem machine wants him back to cooperate with, he is likely to win the primary.

It was enough to just say “I endorse Kevin McCarthy for another term’. He didn’t have to go so over the top by calling McCarthy “Outstanding”

I believe that Trump himself called in "outrageous hyperbole" in the Art Of The Deal. McCarthy has been far from "outstanding", and there was no reason to write that, since it's plainly false.

Trump hurts the MAGA cause when he praises those milksop Republicans who openly fight against conservatives.

He certainly confuses his base. I would much prefer that Trump state, "I endorse McCarthy because he's the least bad California Republican in that Congressional district". I prefer blunt honesty to B.S., but that's just me...