[PantsOnFire]

I'm no expert but here are some reasons I can think of:

1. Any time you call, you have 0% chance of winning the pot outright. Thus, calling is a passive action whether its cold calling, limping or calling a flop bet.

2. Cold-calling keeps control of the hand to the raiser. If you re-raise, you take control of a hand and have much more fold equity and credibility for your actions on the flop.

3. If you figure you have a better hand than the raiser, but call anyways, this is not cold-calling but smooth-calling and is a deceptive play. Cold-calling is done with an hand equal or inferior to the raiser's range and thus you simply hoping to get lucky and catch up.

4. When you cold-call, you give players behind you better odds to call so you will usually end up with more competition. A re-raise will cause more folds behind you and a better chance that you will play heads-up with the raiser or even win the pot uncontested.

5. The EV of cold-calling depends a lot on your hand. Cold-calling with a small pocket pair isn't as bad if you expect callers behind you and no raises. Cold-calling with a hand like AJ or KQ is much worse and may get you into trouble.

6. Keep in mind that cold-calling usually refers to the first player to call a raise. After that it is called an overcall which can be bad as well be not nearly as bad as the cold call.

7. Also, I don't believe cold-calling is as bad against a LAG habitual raiser but this is solely due to the Gap Concept. However, again you should be re-raising this LAG player a lot and not always cold-calling him.