This might seem stupid, I've not told many people this.
I was once in a Judo grading.
Full of confidence.... First fight, caught my little toes in a space in the tatami just as the other guy hit (kicked) my foot. Sprained ankle, had to retire from the fight.
Waited twenty minutes... took another shot.
I'm 128 pounds, next guy is 230, turned to throw him, sprained ankle gave way, he fell on me, two cracked ribs.
Sat a while with my arm tied up, went in again. The next guy, big army boy, leaned on me and it hurt my ribs too (TOOO) much, gave in (disgrace).
Went straight back out, 5 minutes later.
The next guy caught me...perfectly.
Went home, hobbling, in tears, consoled by my (soon to be) wife.
Wouldn't take a taxi, insisted on walking. Had to walk.
Best thing that ever happened to me.
All I remembered afterwards was trying to cover my weakness, and that last guy footsweeping me perfectly, it was just beautiful. It took me a while to appreciate though.
Still don't totally understand why it was the best thing ever for me... but it was.