You should always give yourself an opportunity to fold if the situation dictates.
For example:
If losing the hand is the difference between little/no cash versus decent cash, at least consider whether you should lay down.
But really, you need to consider the flop. A paired board is problematic...especially JJ, QQ, KK as matching cards are very much in your opponents range.
Similarly, boards with straight combinations need to be considered.
Then you need to consider the flop in context of what you know about your opponent.
Generally, I'd still want to see the turn, when holding AA just to be able to count my outs if I was to call the river.
poker stars seems to grant sets of aces every 15 mins or so...
Finally...if this is a multiway pot, and I'm out of position and villains are raising, I'll consider the risks...
Bottom line: do not get married to your starting hand. Re-evaluate after the flop to be sure you can reasonably contest the pot.
Cheers,
ObbleeXY