Part: Part Five - Betting Before the Flop

When your bluff gets four-bet

Pre-flop
Blinds 100 / 200Pot 7,300 (36.5 BB)BBA♠5♠● 25,000 (125 BB)YOUyou 3-bet to 1,800 as a bluffBTN● 25,000 (125 BB)Button4-bets 5,200 (26 BB)SBfoldsD

You light three-bet a button steal to 1,800 with A♠5♠ as a bluff - and he four-bets to 5,200.

Your light three-bet got four-bet. With A♠5♠, best?

WhyYou put the three-bet in to make him fold, and the four-bet is his answer: it didn't work. Now you're staring at a value-heavy range with A-5 suited and no position - nothing to profitably continue with. Adding a call or a five-bet just throws good chips after a bluff that already failed. A five-bet re-bluff exists against the right opponent, but folding is the default.
What happensYou give it up, out only the three-bet. The skill isn't the aggression - it's recognizing the instant it stops being profitable and shutting it down cheaply.
A light three-bet is a bluff, and a four-bet means the bluff failed - so you fold instead of compounding it out of position. Knowing when to abandon an aggressive line is what keeps a busted bluff cheap.

A light three-bet is a bluff bought on fold equity - when a four-bet answers it, the fold equity is gone and so is your reason to keep firing; folding caps the loss.