Most of the murderers on Columbo were arrogant jerks, and it was kind of fun to watch them get taken down by Lt. Columbo. However, once in a while there was a murderer who came off as relatively sympathetic. They were otherwise decent people who were driven to desperate measures by their victims (Johnny Cash in “Swan Song & Donald Pleasence in “Any Old Port in a Storm” come to mind).
For me it’s not as much fun to watch an episode with a sympathetic murderer because I find myself almost rooting for them. Obviously though, I know they’re not gonna get away with it in the end, so it’s kind of a bummer.