If you spend an hour every day reviewing the code and making design decisions, you could very well hire monkeys and they would come up with good code. You have to micromanage the code to get good results.
I haven't outsourced any projects so far. I have, however, worked on a project launched with an off-the-shelf script - it definitely saved time and effort upfront, but the code is far from great, so it's been more frustrating over time. I still haven't decided whether the tradeoff was worth it.
Have you actually used this strategy yourself, and if so, how did you make it work?
On seeing your first comment, I sort of knew where this was going..
Looking at horrible code produced by your cheap rent-a-coders won't make it any better - making it yourself might.