Who never climbed, never fell.

A setback can be a consequence of making an effort. Someone who never undertakes a difficult task may avoid failure, but has not faced the challenge either.

The proverb puts a fall in perspective rather than treating it as proof of foolishness or inability. It contrasts the visible mistake of a person who tried with the safety of a person who did not.

Use it to console someone after an unsuccessful attempt or to temper criticism of a person who took on a difficult task. It is less apt when the point is to assess whether the attempt was prudent.