A bad trade is like bad trip. You only realize it's a bad trade after you close the trade. It's like taking a bag of cash and burning it. It's like doing some bad LSD. Try not to remember the bad trade,,nigthmare trade.
Depends how you trade, I know fairly early on if my trade will work or if it won't. I trade on a very fast time frame and get feedback very quickly. I don't need to exit to realize if I made an error, the reason I DO exit is BECAUSE I know I made an error.
a lot of times a bad trade just happens. for example, something might work 9 out of 10 times, but it is that 10th time that gets you!
A bad trade depends on one's feeling. Some people feel uncomfortable to cash early profit and feel satisfied when they exited early avoiding widened loss; while other feel happy with early profit and having very small number of losing trades. The latter is a disaster.