Try to imagine our brains like cell phones or computers, etc. It has temporary memory space, besides that it also has long-term memory storage. This temporary memory space is limited and relatively smaller, than long-term stored memory.
If on your phone, this temporary memory space is used by some running apps, and can slow down if they start getting full. Likewise, our current minds are filled with various information, inputs, sensations, sounds, visions, images, thoughts, memories, and so on. Makes it hard to focus, do the right thing for future goals.
If the temporary memory space of the brain begins to fill up, life becomes restless, emotional, impulsive, a lot of desire, ambition, or even dislike, also fear, anxiety, difficulty thinking clearly.
So, it's time to clean it up, like freeing up temporary memory space by closing a running program or application. So the brain needs a vacation, don't think about this and that, just concentrate on enjoying our breath.
When the mind, conscience, mental images start to appear again, refocus. Don't forget the breath, keep your attention on the process of the breath and its sensations.
When other thoughts begin to reappear, return the awareness to the breath again. Don't feel sad, upset, and or disappointed if his attention is easily distracted, this is an opportunity to practice.
The repetition draws the attention back from the mind to the awareness of breathing, further strengthens concentration, increases mental energy, such as freeing up temporary storage space in our muscles, being able to focus and being able to deal with distractions.
The mind becomes calm but strong, is not easily tempted, is provoked by emotions such as hatred and anger, and the brain can think long. This psychological exercise is also good for discipline, creativity, and willpower to resist temptation and pain in the mind. The brain becomes more optimal, a lot of mental energy can be utilized, used for a better and happier life.