Failure May Come if.....

What will make you fail in a race, ride or event?

-dehydration or overhydration
-non-water fuel isn't sufficient or you cannot digest at rate demanded
-pace is beyond your Lactate Threshold (LT) for too long, you lock up
(Lactate can come from any muscles undertrained or stressed causing failure everywhere!)
-technical ability is lacking or fail from crash
-come into race overtrained or muscles not capable of event demands

Prevent with knowledge, experience and/or training. What else?