What about opening a car loan when you don't have one? My credit score went down when I paid off my car :eeK:, because it says that multiple types of credit help my credit score, and paying off my car got rid of one type of credit (since I don't have any other credit besides credit cards and charge cards).

And the other point is it's not cumulative. Many of these things only harm you temporarily, so doing them over and over and over again (the churner's world) does not make youf credit get progressively worse, it just means it stays around a plateau that might be a bit higher if you were doing none of that churning activity (or anything close).

But that's also in abstract: The opposite of someone who's a churner (who's typically very concerned about maintaining good credit), is someone who has very little credit, hardly ever applies for credit, but gets behind on it occasionally. That person may have done very few of the things you said hurt "somehow", but of course they end up with a way worse score than the churner who's doing a lot of the things you say hurt "somehow".

So IMHO it's not enough say it hurts "somehow", but you have to say "how much" and "for how long" to put it into perspective. And that's where the credit changes that are common in the churner's life aren't so bad, compared with things like being late on payments, maxing out your credit cards, having very little credit history, etc.