Very few of us limp preflop. When you raise preflop, it's important that you take what's yours. You've built a pot, and you need to be very careful about abandoning what you've built. That's a quick way to turn a profitable situation into a losing venture. When you raise preflop, you're normally wanting to get into the bread and butter situation where you're in a bigger pot and playing in position. This gives you the initiative in the hand i.e. your opponent is responding to you instead of vice versa.
Having said all that, if you just go throwing money in the pot in bad situations by cbetting 100% of the time, you're certainly going to be losing money. Cbetting well is going to take some experience and critical thinking about the game. Of course, there are 2 reasons for cbetting: value with your good hands and stealing. This certainly is an art form.
Value: Many players I coach do not cbet for value nearly enough especially those at micro-stakes. When you're against weaker players with wide ranges, even a middle pair good kicker can be good for 2 or 3 streets of value. The idea of pot control is often taken too far and players miss out on value because they consider their hand to be marginal. But, they often are thinking about their hand strength only as it looks on a poker hand chart. Our hand strength isn't a static thing; it changes based on our opponent's range of hands. If our opponent can have loads of combinations of bottom pair, middle pair, and top pair hands, then our middle pair strong kicker is actually quite strong. Understanding your hand strength compared to your opponent's range and then betting accordingly is going to take time and experience. Certainly posting in forums like these will help.
Stealing: Your ability to steal postflop is based on quite a few variables: your opponent's strategy, how the board connects with the opponent's range, your position, how the board connects with you perceived range, the stack to pot ratio, your image at the table, etc. Some times you have to consider all of these, and other times only a few. For example, if your opponent is very fit or fold on the flop, you can quite simply bet with anything on many flops. An exception might be if you consider his range to be very heavy with broadway cards and the flop is something like AJK. Then the flop has just hit his range too hard to steal.
So yeah... an art