This misconception is probably the most common of all. When it comes time to lose weight, the first step that pops into everyone's mind is to keep caloric intake to an absolute minimum. If you want to drop some weight, this is not the way to go. The human body is a complex system and unfortunately it will take a little more effort to outsmart it and drop that excess weight.
After drastically reducing caloric intake, the body senses that it isn't receiving an adequate amount of energy and nutrients. In response to the significant nutritional cutback, the body slows down  its  metabolism to conserve the food that it is receiving. For this reason, many individuals are still unsuccessful in their attempts to lose weight.
Worse yet, you can lose highly metabolic lean muscle from doing this!

A better approach would be to gradually reduce calories over an extended period of time. The dietary adjustment won't be as drastic; therefore the body won't produce the same reaction.
If you have been working out on a steady basis and trying to keep a close eye on what you eat, but you still can't achieve the physical appearance you desire, then take a careful look at your lifestyle to see if you are committing one of these common mistakes. One (or more) could be all that is standing in the way of gaining a firm grasp on your fitness goals.