Sure, everybody gets to know that their move is bad after they have played it especially in critical positions where you need to be most precise and accurate.
Only Notice Bad Moves After They're Made
I honestly don't know, but I have an idea.
The most common type of learning is visual learning, which means people will leanr best when they picture them. Chess is not only no exception, but visual learning skills are basically required for game play. When one is about to move, one tries to picture one's moves in order to see the variations better. After they move, they suddenly have a change of mental image, and generally can identify and avoid opponent tactics instantly.
This is why it is standard for there to be rules against touching a piece, putting it on all the squares it can move, suddenly realizing the opponent's tactics, and changing the move. It is just how people work; of course they are going to realize it was bad after they dragged the piece, or hit "submit move" or "submit vote." For online and vote chess, the problem is easily solved by using the analysis board. (not computers checking it for you, however.) I use it on all of my online games. This allows you to play little games against the theoretical opponent that is yourself, which serves as a great check.
For live chess, using an analysis board is extremely inconvenient, so my suggestions are.... 1. play slow live chess. Hey, if blitz is your thing, no big deal, but with slow you can spend up to 5 minutes calculating, and analyzing at a time. (But no doubt, your opponent is doing the same.) 2. Don't grab! Beware of grabbing. You can get burned really badly by grabbing, and so you must analyze each pawn you grab before you play it, realize it is a bad move, and are done. Let me show you what I mean.
I often do this. I'll put so much thought into a particular problem, analyze a great deal over the appearance of the current board, but once I make my move, it is only then that I instantly realize (even before my opponent makes their move) that I could have done something way better.
Just looking for sympathies I suppose. I'm sure I'm not the only one who does this from time to time. It just makes me wonder is all.