11 Powerful Mantras for Those Who’ve Lost Motivation

Scott Jurek's "This is what you came for" is one of my favorites. It's much easier to relate to when you're in the middle of an adventure, versus chaos at the office, but perhaps you could alter it there to "This is what you can handle that others can't". My other two favorites: "The only one who can beat me is me" and "Embrace the process, step by step."

It's a short list and worth a quick scan, so you can have a few mantras filed away for when you need them!