Do you know this by personal experience?
Yes. I remember a friend of a friend who had a loaded T-top Buick in the late 70's. After he figured out that he couldn't afford the payments and insurance, he started abusing the car. After he figured out that wasn't going to get him out of the situation, he totaled the car on purpose.
My uncle used to work for Ford and back then a lot of the execs had new company cars on 9 month rotations. Some of them used to brag how many miles they put on before changing the oil.
I worked with a guy who ran his engine out of oil and seized the motor, even though he checked his oil regularly. Unfortunately he was under the impression that the transmission dipstick was the crankcase.
When I sold my '98 GT to a couple they didn't bother to negotiate my price down. The reason? Mine was the tenth or so car that they looked at, and the only one that wasn't all hacked up with poorly done modifications.
I could go on with this but one final: when I bought my current Mustang every one I saw was modded in some dumb way with, and the one I chose was no exception. I spent more time fixing those problems than I did replacing the suspension.