Yeah, I've never had an issue with sound quality and I use the iPad version. The problem is it's limited functionality, as VCMG said. There's a lot of things you simply cannot do in it.

I don't think GarageBand makes lower quality audio, I think the problem is that it's pretty limited in comparison to other audio programs.

TL;DR -  What is it that causes everyone to say garage band sucks exactly?

I think everyone here is familiar with people saying "garageband sucks" and "garageband messes up sound quality" and stuff like that. I am just curious if there is really any validity to those comments, and if so... What is the exact reason that garage band produces lower quality than other audio programs? Like, is the program somehow handicapped? or is it just user's using the default options in the program that cause the sound quality to be worse?

The main reason I ask, is because I am looking for the motivation to start learning ableton live.. so I can switch, and possibly make higher quality music...   But I will really need a reason at this point, because I know garage band pretty well, and I have it all setup with a lot of custom instruments... Whereas on ableton I will be starting from scratch, and its a bigger/ more complicated program, that I have only about 5 hours of experience with.