Starting out in Limit

[JH1]

OK that makes some sense to me. So is this correct:

You make money in limit when you realize that your made hand or draw is not the best and fold, saving bets.

It just didn't make sense to me before how you could have winning players because if there multiple players in pots all getting 5:1 a lot of the time or better, they are almost always all correct to call, therefore no one is making mistakes and therefore everyone should be a winner which does not compute.

This is why I thought a winner would be whoever's side variance was on for the day and I may as well be flipping on NL tables if we're all going to show our hand down anyways.

One more question, I read a post, I think by Ed Miller, that you should not be folding a reasonably big hand in a large pot for one bet. Is this true? ie. don't fold a set or a straight on a 3 flush board, etc.