Dev environments and various software conflicts, obviously. ie. You’re a noob dev and you need python 2.x.x but your mac os install has a different version and

Dev environments and various software conflicts, obviously. ie. You’re a noob dev and you need python 2.x.x but your mac os install has a different version and you’re too noob to understand what’s happening and the reinstall fails because xyz. Huge barrier to noobs. Programming is really quite trivial, fighting through external bugs like this is not.