In working with tens of thousands of traders over 20 years I found these simple truths:
You guys undertrade large size with much more expensive stop-loss cost than needed, and do so on marginal setups.
It is much smarter to take 10 $100 stop losses than one $1,000 stop loss. Understand that completely and it can make a big difference in your trading, potentially.
Also, range and price action are everything, along with trade management. Look to trade the outliers, the corners, not the common.
A word on over versus under trading. You need to look at trading like a game of Pac-man in which you're eating a lot of dots, not making a single big trading decision like going to a buffet. The law of large numbers needs to work for you, and it can't if you're not giving yourself enough chances to make winning trades. I'm perfectly fine doing 200 trades in a week of which 150 might be stops and 50 wins, as long as the profit from the wins outdoes the cost of stops.
Back in the 90s I would trade larger size infrequently and it would be like I'm about to make a big trading decision, drum roll. Nowadays I look at any trade as though it were the next of the next ten thousand and I genuinely don't care about how any single trade works out, instead I look at a week's worth of trades at a time. If you worry about any single trade, that means that you're trading too much size.