Evils.

It's about perspective.

Let's say you have to fire one guy and your two options are a guy who lies about important work related things and a guy who is stealing from work, which would you fire? You have to weigh their crimes and decide which is worse. The one that is less bad would be the lesser of two evils, though they're both pretty awful.

It's not always obvious nor is it ever an easy decision. Elections are typically about choosing the lesser of two evils because all politicians are truly evil.

Bad example, i'd fire both.

Brb looking into the classics for a really solid example.

Wikipedia pulls through again.

"Better the turban than the mitre", used by Orthodox Christians in the Balkans during the rise of the Ottoman Empire. Conquest by Western Roman Catholic powers would likely mean forcible conversion to the Catholic faith, while conquest by the Muslim Ottoman Empire would mean second-class citizenship but would at least allow Orthodox Christians to retain their current religion. In a similar manner, the Protestant Dutch resistance against Spanish rule in the 16th century used the slogan Liever Turks dan Paaps (better a Turk than a Papist).

At it's heart, it's a principle. In my opinion, a poor one. If all the choices left are evil, than an evil choice must've already been made. Sometimes the best solution to a current problem is to remedy a past mistake.