How exactly does skin picking relate to ocd?

I used to do this with my face for years (I had horrible acne and this led to significant scarring but I couldn’t stop) and now I don’t pick at my face anymore but I pick at the skin around my fingers. There’s not really an obsession related to doing it so I don’t even know if it has anything to do with ocd but I see a lot of people here mentioning it so I was curious.