70% accuracy + Speed is better than perfect...

Artemgy has an interesting post about agile decision making.

"...it is important to make the right decision… …or is it?
Not according to Percy Barnevik’s “7-3 formula”! The man who ran Swiss engineering giant ABB for a decade insists that you can still be successful if you make nearly half as many wrong decisions as you make right decisions!"

I think a big part of embracing agile is understanding the fail quickly mantra. You have to accept the boundaries of your day, iteration, and release and use them to force forward progress instead of falling into an analysis paralysis state. This is a by-product of all the feedback loops found in agile (pick your agile denomination). It's okay to make bad decisions sometimes if you can recover quickly.

The more transparently you can do this, the more trust you build with your customers and users that you will always do the right thing for them in the long run. This creates loyal followers.