My main point is that of improving the way developers think. By having instant gratification from someone already answering it, on SO for example, then the developer doesn't really learn how to actually solve problems. The end up relying on someone else to have already done the leg work for them. So whilst potentially more could be done in the same time frame, less problem solving skills would be developed.
Don't get me wrong, it has it's place and can be quite useful at times; as mentioned, use SO if you've been stuck for a while. Before any of this however, devs should just read their code. So many mistakes come from not reading their code and expecting it to run first time when a spelling mistake has occurred or some other trivial thing.
As slight side note, I also don't like SO due to the environment it creates and the lack of updates to questions. As an example some questions have been on there 10 years, which we're useful at the time but now are redundant and should therefore be removed but won't be.