Meditation is not about keeping your mind in some sort of catatonic state. Nature loathes a vacuum. Meditation is all about 'sati' - awareness. Being aware of where the focus of your mind wanders and learning to take control of that focus. The observing of your breathing in meditation is merely a device used to catch your mind change focus.
Nature loathes a vacuum, and keeping the mind still is like keeping a beautiful car in the garage.
It was designed for movement. The idea is to get the car onto the road and move. Now, it is important that you, as the driver, have total control of the car and not allow the car to have total control of you. It is exactly the same with the mind. To gain control over the mind we must become aware of how it works.