There are many reasons to not move from your current situation:
Fear is the worst... fear stops you from achieving true greatness! I always try to go for the very best and i never stay in the "good enough" part, everyone can be average, everyone can have the "good enough" but only true hard workers can achieve the best!
Fear can be a tough one to beat, but if you're able to do enough research that you feel comfortable moving forward with a decision, it can be beneficial and liberating for you.
Keep being the best, @teutonium!