Never say 'I could have done that,' because you didn't.

It's very easy to say, 'I could have done that,' after someone's done it. But I did it. You didn't. It didn't exist until…

— Damien Hirst

I don't want to be the guy who said 'I could have did this, and I could have did that.' I want to be…

— B. J. Penn

Everything people say I couldn't do I've done.

— Floyd Mayweather, Jr

When you say, 'I can’t do that,' you're expressing yourself incorrectly. You should say, 'I couldn’t do that before.'

— Leo Tolstoy

“Could've, should've, would've. Didn't.”

— S.L. Grey

You never know, when you commit to something, what else could have been. I'm so bored with that concept anymore. 'If only I didn't…

— Gary Cole

All the time you're saying to yourself, 'I could do that, but I won't,'--which is just another way of saying that you can't.

— Richard P. Feynman

“Ah, how I rue that what I could have done I did not do!”

— Ludovico Ariosto

“Don't you dare feel sorry for 'could have'.”

— J. Kenner

There's always something that you go 'I should've done this better, I would've done that.'

— Bianca Del Rio

You shouldn't have done that.

— Anonymous

I did it because I can,I can because I want to and I want to because you said that I couldn't

— Innah Delos Angeles

If I could have done anything more, it would have been less

— Artie Shaw

“Could of, should of, would of… didn't”

— Kristiene Gray

You shouldn’t say I can’t until you’ve tried.

— Patrick Henry Hughes