Once a goal has been set, discipline plays a critical role in a person's achievement of what they intended to do, since strict adherence to plans and ideas determines whether you reach your goal and how quickly it will happen.
Everyone intuitively understands that certain skills are acquired very easily and quickly, following a clear and rigorous plan, and only a small percentage of people begin to use it. The rest, a much larger mass of people prefer to "go with the flow" in life, explaining their failures by the fact that they are too impatient, lazy, and so on.
No wonder they say that unwillingness has a thousand excuses, and desire has a thousand possibilities. And you just need to set a goal and start moving, applying discipline along the way. Let these be small steps, but over and over again you will begin to achieve results, because all great things started small.
Discipline determines which decision you will make at any given time in your daily life. Do you exercise or lie in bed? Read an interesting book or watch a reality show? Eating a salad in the evening or throwing sweets on your belly can make a huge difference in the long run.
It is also very important not to confuse the concept of "discipline" with what many understand as limitation. Being disciplined means acting according to a plan, consciously choosing your steps in one direction or another. All this in order to achieve what you want. Take action as soon as possible, and let what you want become reality!