Dopamine has its existential value for human life and health. But if people overactivate this mechanism, it can easily "crash" our brains, like a scales out of balance.
When a large amount of dopamine floods into people's brains, although people will feel excited for a short time, the long pain that follows will follow. When the brain gets used to a stimulus, it becomes numb and requires a higher intensity stimulus to reactivate it. If people repeatedly pursue the same desire, they fall into a vicious circle and this is the beginning of "addiction"