You searched for: “aut non tentaris aut perfice”
Aut non tentaris aut perfice.
Either don't attempt it or else finish it.

Also translated as, "Don't start anything you can't finish." Although it is a bad habit to leave things half completed, it is probably better to cease working on anything that will obviously result in failure.

This entry is located in the following unit: Latin Proverbs, Mottoes, Phrases, and Words: Group A (page 20)