Yeah, measuring anything is hard, and then Goodhart's law kicks in.

I have a rental income and, for the same reason, hardly ever raise rent. When a tenant moves out, I raise it for the next one.

Could you talk me through it on your side? Are renters hard to get, so when you get a good one you want to be maximally nice? I have a friend who has a lot of rental properties, and his motivation is a combo of what I said + pity. He's been taking a loss for more than a decade on one place, but the renter is nice and has few options; and the place is gaining equity, so he can be philosophical about it.