The mind is like a monkey, keeps jumping between past and future or the fantasy channel.
Alan Cohen says
The lawyer whom you pay the most. The way you pay these lawyers, however, is not with money; it is with your attention.
Where your attention goes, your mind & energy flows there.
Your mind plays a major role in holding your current attention.But your mind is always on an excursion mode.Mind keeps traveling between your past and future or to the fantasy world.
Hence, your attention keeps wandering.