Why do first loves basically break up?

Beautiful first love, most people will basically break up. Why? I think there are three reasons:

Mr. Jin Yong has a saying in "swords and swords, love and hatred": "The depth of love will not last long, and the weight of wisdom will hurt", to the effect that feelings that are too devoted and too valued cannot last long, and people who are too smart will easily see through the world and realize more indifference in the world, which will hurt their health. Just eight words tell the cruel truth about feelings and life.

First love often happens when we are still students or just entering the society. At this time, our three views and plans on life and the future have not yet taken shape, which is very unstable and will be affected by various factors. The values and life plans of both sides are easily misplaced with each other's growth, and it is difficult to go on because of the long communication time and the inability to reach an agreement. Even if you give a promise to ta, it may be difficult to really do it, but it's nobody's fault. Commitment is often a temporary sincerity, and later all kinds of helplessness are forced by reality.