My Professor and mentor, Royce Gracie, said this many times during our Jiu Jitsu training:
“The belt only covers two inches of your ass. The rest you have to cover yourself.” ~ Royce Gracie
I have many BJJ and Muay Thai related quotes that I find inspiring, including “steel sharpens steel” (aka - we all help each other get better, sharper.)
As well as “The mat never lies (also spoken as…the mat is the great equalizer)”. When someone says they’re a bad ass…you can’t hide it in Jiu Jitsu…when you get on the mat, every weakness is exposed. If they’re a bad ass, you will know it very quickly. If they’re not, they’ll find themselves tapping (or going asleep) to someone they thought themselves better than.
The only one I can attribute to someone else is the first one that Professor Royce says many times. The others I’ve said thousands of times myself in my BJJ / Muay Thai journey.