Here's a fairly typical hand in an 11/27 that illustrates a couple of concepts that you grasp with experience (or one concept with two parts, I guess).
NL Holdem $30(BB) Poker Stars Game#46704987178
FR Vessant ($1,610)
nETP_XPYMOB posts (SB) $15
Shpuon posts (BB) $30
Dealt to FR Vessant As Ks
I have AKs. A strong but not made hand.
wheel_me62 calls $30
ae0066 calls $30
Two fishes have limped and many players are tempted just to limp behind. The fish don't fold they say. Then you miss the flop and you've wasted your raise.
FR Vessant raises to $150
JKoenig99 calls $150
fold, fold, fold,
wheel_me62 calls $120
ae0066 calls $120
And yes, not only do the limpers call, but another fish does too.
FLOP ($645) 5d 7c 3c
And I whiff the flop and will check/fold.
FR Vessant checks
JKoenig99 bets $330
This bet will very likely take it down. It doesn't really matter what bettor has although he can actually have a pretty wide range.
FR Vessant folds
JKoenig99 wins $645
So that sucked, right?
Well, here's the thing. Look at the pot size on the flop. It's pretty decent and that means that the times I hit, I'm going to find it very easy to get it in. Had I limped, the pot would have been much smaller and I'd possibly need all three streets, giving villain three opportunities to decide his shitty hand was not worth pursuing. Now I can commit villains on the flop and get them in on the turn, and often all the money will just go in on the flop.
And here's the second concept. Often the money will go in whether I hit or not. The other guys will now often be inclined to stack off, where if it had been a limped pot, they could keep it smaller. This is probably more of a benefit in 9mans but it's still useful.