Early in SitnGos you should really be folding stuff like AT in early position, you can raise with them in late, but dont get too dedicated to them. Same thing with lower pocket pairs and suited connectors.
In my opinion the biggest trouble hands are low suited connectors and big pocket pairs like KK and AA, if they're misplayed preflop or even played perfectly sometimes pre and post flop, you can still lose with them.
Example: KK early position early in an SnG, raise, everyone except BB folds. The flop comes QT9, BB shoves and with an overpair and a gutshot you call. The BB turns over T9 suited for two pair and the turn and river do not help.
Did you really misplay the hand? No, but these kinds of things happen and have to be accepted. A pocket pair preflop is still just a pair.
Another example, you are dealt 4h5h preflop on the button, several limp behind you and you decide to also limp with small blinds and position. The blinds both come in and the flop comes AK3 with two hearts. Someone raises and you and one other comes along. 3 go to the turn, which is the 8 of hearts. You shove, the original raiser folds and the other person in the pot folds. He turns over Th9h and you are drawing dead.
Again this hand was not really misplayed, chasing a draw is not always correct with implied and pot
odds, but more than doubling up with the flush can be too tempting. This is where BR management is important, so these unlikely but possible situations do not destroy your roll.