Why does the mind wander all the time?
It doesn't wander all the time. When you like something, your mind is just fixed there.
Suppose you are watching a movie or television series, does it wander all over the place? No! For two and a half hours you are focused on the screen. You are sitting watching the movie and you are so immersed in it, tears come out of your eyes, and you roll and laugh.
I don't think your mind is wandering all the time. The mind sticks to what it likes. Where there is some attraction, where there is beauty, where there is love, where there is truth, the mind automatically floats there.
When you learn about the mind through yoga and meditation, you will know how you can bring your mind to the centeredness, the focus that you very much want