Patience is the willingness to persist and persevere. Patience is needed to learn, to accomplish, to develop our character, and to interact harmoniously with other people. Chronic impatience destroys one's life. Even milder forms cause considerable pain. Impatience causes stress which is harmful to one's health.
Impatience breeds anger, leading to heated arguments and quarrels.
Impatience greatly limits what one will learn and accomplish. The essence of patience is to live in the present. We are impatient because we want to be in the future faster than reality will take us there. Realizing that we are where we are because it's the Almighty's will for us to be there now will enable us to be calm and utilize waiting time more effectively. Since we will generally be in the exact same place whether we will experience patience or impatience, it makes sense to choose to be patient.