Goodhart's law on citation count... Too easy to game. It seems many people do this, and it works for them, because even if their peers just know who is doing it, they're still making bank, see Didier Raoult's paper mill.
See also: The Retraction Watch Leaderboard. Who has the most retractions?
https://retractionwatch.com/the-retraction-watch-leaderboard...