Gut instinct

Why is it that some people (i.e. Me) just wont follow their gut instinct? Your gut says do 'A' and you'll be ok, things will work, but your stupid brain says do 'B', dont listen to your gut, be sensible about this. Being sensible normally means I make the wrong choice, my gut is always right, but I never listen to it. Why?

I also bought some foo fighter CD's and DVD's on play.com this morning, click, click, click, and I bought it. Way too easy, but thats not what I'm talking about, thats just my bad spending habit.