Lots of Prohibition was driven by good intention, especially from religious sources - the Baptists.
However, it was also driven by bad intention. Who stood to gain when alcohol was made illegal? - the Bootleggers.
There can be good and bad reasons to do something, especially when that something is public policy.
https://en.wikipedia.org/wiki/Bootleggers_and_Baptists
https://www.econtalk.org/bruce-yandle-on-bootleggers-and-baptists/