You're absolutely right, being in silicon valley does not, by itself, equal success. There are other factors that are far more important and there is no silver bullet. That's why there are tons of examples of great startups all over the world, including ones based right in my hometown.

So, if you personally have no desire to move here and are happy with your startup right where it is, then you should stay where you are.

All that being said, if deep down you've got the feeling that the valley might be the place for you, you see that you're not moving forward on your startup as fast as you'd like, or you haven't yet found the right people to work with, then it's a move I highly recommend.