When you are building muscles and going to the gym you are always told not to expect results to come in immediately as that is unrealistic. However, a lot of people find that even if they have waited it out they still are not able to get a lot of visible results as their muscles are not showing. The problem is that people feel themselves getting stronger, feel healthier, and feel their stamina growing, but cannot see any muscles to show for it. This is especially true for any person trying to grown some abs.
The thing here is that the muscles are being formed and probably have gotten a lot stronger, but are not visible because they are hidden under a few layers of fat. This problem is often faced by people who do not keep track of their diet but do exercise a lot. The misconception that exercise alone will make sure you have a great body is flawed and often leads to this problem.
If you do reach a point where you feel like your muscles are not visible regardless of how hard you work, then you need not get demotivated and leave the gym. Instead what you need to go through is a fat cutting phase. This is a phase where people cut down on the fat that they consume and lower the intensity of the exercise that they are doing to simply burn the fat instead of growing muscle. The reasoning behind this is that your body needs fats to burn when you exercise intensely so during the cutting phase you need to take it a bit easier. In all this you also need to know what to eat when cutting. You need to have a controlled amount of the right type of foods to make sure its effective.