My understanding – and I’m not a New Yorker – was that he has been often credited with reducing crime in NYC. Part of that was, as I recall, by cracking down on minor crimes, things like aggressive panhandling, with the idea that that was kind of a gateway drug to more-severe crime.
I don’t know whether that approach or him in particular was responsible for it, or whether it was other phenomena at the time – my gut is that changes like that usually aren’t just driven by one person – but my understanding was that crime did considerably fall off around the time, and crime was something that a lot of New Yorkers had been really upset about.