look at it from the angle of "how you handled that last trade, win or lose, can tell you a whole lot". Like, did you ignore your stop and continue to let it go against you...or get out when you were supposed to? Are you trading following your gut and is it working out? are you trading with confidence and discipline?
"how you handled that last trade, win or lose...
Are we talking about the trade, or are we about talking personal traits and trade mechanics?
It's only a question.
Regarding trading, the laundry list of what (controllable things) can go wrong boils down to discipline. If that causes discomfort, than the knowing-doing gap is applicable... which leads back to discipline. If you just don't know, that's controllable. Learn. If you don't know that you don't know, well, in trading, that's a problem.