Why instant refutations don't work!
The reason why many beginners lose their chess games with opponents is because they tend to go for the instant refutation of peculiar moves.
They should always keep in mind that thinking of just one move ahead will not work when playing strong players. The fact that you could go a piece up by refuting your opponent's play instantly will leave you dumbfounded when he finds a counter move.
Here are some games that I played which I've won and lost. I've annotated the games for the better understanding of what instant refutation is.