Fast weight loss diets tend to lead people to think they can drop the pounds in a very short time, and they can but only for a limited period of time. This is why the scale may not be your best friend when you are on a diet; the daily fluctuations can become depressing if don't understand what is happening. Weight loss tips that tell you to focus on fat loss rather than what the scale says are far more useful in the long run.
When people set out to lose weight they become obsessed with how much they weigh; it is called weight loss after all. However it would be far more accurate to call it fat loss since that is the real goal. You can lose weight by reducing the amount of muscle that you have or the amount of water that you are retaining but this is not really a desirable goal. What you want to do is lose the fat and in many cases this does not result in the loss of any pounds. If you don't realize this you can quickly lose motivation when you don't see any change when you step on the scale.
The key reason that you want to avoid paying attention to your weight is that muscle is a lot heavier than fat. Therefore if you are adding muscle, which you should be as part of your weight loss program, you may find that your weight has actually increased, even though the amount of fat that you have has decreased. As long as you are losing fat the actual number on the scale really doesn't matter; this is one of those important weight loss tips that people have a tendency to forget to mention.
The scale can also be misleading if you are on one of the many fast weight loss diets that are so popular these days. The reason is that most of these diets will cause you to lose water more than anything else, at least for the first few days. The result is that you will lose a lot of pounds over the first few days but then things will slow down; this is normal there is a limit to how fast you can burn fat. However if you are standing on the scale every day expecting to see the number go down, it can be discouraging, which makes it hard to stick to your diet.