Question of the Day: Why Are Female Gymnasts Allowed To Stop A Vault But Not Male Gymnasts?

Last night I was watching the women compete in the vault exercise and watched as one gymnast stopped her run and returned for a second try. I was surprised to hear that females are allowed to stop in their run, but males are not. Why?

The Olympic rules state that a female gymnast can stop or break a run before touching the springboard without a deduction as long as they return to the end of the runway within thirty seconds. However, a male gymnast will receive a score of 0 if they do not vault once they start running.

I cannot see any justification for the differentiation (and more favorable rule for females). I am not rushing to file a discrimination lawsuit, but does anyone have a reason other than tradition or arbitrary treatment?