Mind is basically a graveyard. It accumulates & categorizes information & images that are acquired through experiences, and all experiences are of the past. And the past is dead & gone.
The main activity of mind is engaged in thinking of the past. When not thinking of the past, then it is planning for the future, which is only a projection of what has been experienced in the past. Plans are made, goals are set, from an edited version of what has been experienced in the past. The negative is edited out and the positive is projected as a goal to be achieved at sometime in the future.
Mind functions most efficiently with that which it is known & familiar with. Efficiency drops in unfamiliar environments & new situations. And becomes dysfunctional when attention is needed in the present moment.
Consider the mind to be like a large room that has bookshelves making up its four walls. Selected information is accumulated onto those bookshelves. The center of the room is empty. This emptiness in analogous to the ego, as the ego itself doesn't really exist, but only appears to be real because of the accumulated information that is contained on the walls and later referenced to. Ego gets its apparent strength from this referencing to that information.
When new information is received that runs contrary or in conflict to that which is stored on the walls, then the walls will begin to tremble. The house will shake, as Ego will consider itself to be under attack & threatened. And with that, ego will lose its prowess, confidence - it will think itself vulnerable.
In order to regain its formidable strength, it will have to discount, discard, discredit, rebuke, the new information that threatens its existence. Or simply get angry & make war to those that have brought these threatening ideas.
Mind cannot exist in the present moment. Being in the present means certain death for the mind-ego. That is why mind cannot let go of the past. Its entire pseudo existence is based on it. Mind & being are diametrically opposed to each other. That is why meditation is scoffed at and made jokes about, because it is the ego killer. Attachment to old beliefs, concepts, ideals, individuals, objects, foods, drugs, etc. is an addiction. It is a habit that can be difficult to break, but not impossible.
Continuously living in a graveyard cannot be considered much of a Life.