Quitter (noun)

A person who gives up easily or stops trying when things get difficult.

Origin:

From old french quitier "to release, acquit", from latin quietare "to quieten, pacify".

Examples:

1. I"m not a quitter, I"ll see this project through to the end.
2. He was labeled as a quitter by his peers after he dropped out of the marathon early.
3. She"s no quitter, she"ll fight for what she believes in.
4. The team was disappointed when their star player turned out to be a quitter.
5. He"s not a quitter, he"s just facing some personal challenges at the moment.