Why do people hack?

From what I understand it's just to ruin someone's experience and to get a reaction out of them. That's why some people boast about hacking because they know for legitimate players this can be rage inducing as oftentimes can completely affect the outcome of a game and a majority of hackers find this hilarious.
Not only that but it can be a way to advance beyond what can be done normally. Especially in CSGO if you are a shit player or just unable to get out of your current rank, hacking is an alternative that can be used to rise beyond your normal rank and in a fast time.