Raising Preflop

A lot of players don't raise preflop and don't understand why it's important.  In fact, one of the most common game types that you'll see is a game that's very passive and loose pre-flop, and then ordinary afterward.  By that I mean there are a lot of players just limping in preflop.  First of all, how do you play in a game like this?  You can play a lot more drawing hands, primary Axs (suited aces), and pocket pairs.  In late position with a lot of limpers ahead of you, you can play almost any two cards.  Basically, people with better hands preflop are not betting (as they should), which allows you to see flops cheap and draw to beat them.  Because a lot of people saw the flop, you need to make a pretty good hand on the flop to continue, so you're going to tighten up at that point.  You want to make a flush draw, a set, two pair, something like that, even top pair with an Ace kicker is not good enough to play strongly.  You're only paying one bet to see the flop, so you're getting good odds to see it and possibly win a big pot.  Note that you're not winning a lot of hands, but when you do win, it's a big pot.  People with very good hands will find you cracking them with apparently crazy starting hands.  In this situation it can appear that you are playing junk and playing badly - that's a good image, you should allow people to think that.

Now, what if you're in the other situation?  You have a pretty good hand, and you're considering whether to raise or not preflop.  You should raise, but why?  What if you don't?  A lot of people think that you should wait to the flop, wait until you see that you're ahead.  Well, there are a lot of problems behind that thinking.  For one thing, you are almost never a big favorite in poker.  If you do make a big hand on the flop and bet, your opponent will probably fold, or call with good draws (eg. flush draws) or raise with even better hands!  Only very rarely can you make a big hand when your opponent will also pay you off well.  Say there is a 10% chance you make a big hand, and a 10% chance your opponent makes a big hand, then the chance that you can get paid well is 0.1*0.1/2 = just 0.5% !!  (we divide by two because half the time *they* have the better hand!).  So, trying to get into a really dominating hand is not a good way to play, when you have a good advantage, like a 60-40 advantage, you need to get your and your opponent's money in the pot.  So, why should you raise?  Well, you probably have the best chance of winning, so when worse hands call your bet, you are making money.  You are betting based on the idea that worse hands will call you.  Some people think that by betting you make the pot smaller, but that's not so true.  If you get 6 callers from a limp or 3 callers from a raise, you're getting the same amount of money in the pot.  Furthermore, you are reducing the field, which gives you a much better chance of winning.  You'd much rather beat people by having them fold rather than having to actually make a better hand against them.  Finally, you are taking the lead in the pot, showing strength, which will be a big advanatge on future rounds.  It will make it harder for others to bluff you out of the hand, and make it easier for you to bluff.  What if you don't raise pre-flop?  Well, for one thing you are allowing a lot of people to see cheap cards against you, so you now have to make a very good hand to be confident.  For example, if you have AK and don't raise and many people limp behind you, now making just a pair is not a very strong hand.  Also, by just limping, you are not setting yourself up well for future rounds.