Why is it that you do exercises
and rush through them? Are you simply trying to get them over with?  Why do them at all?  In doing a thing quickly and shoddily you
barely reap the benefits.  We use this as
an example, but it applies so much to human nature in general.  You go to great effort to start an activity,
and then you shift your focus elsewhere or do not apply yourself fully.  The result is less than optimal.

If you are going to do a
thing, be with it.  Notice how often ego
tries to distract you, keeping you always seeking greater pleasure, when the
greatest pleasure is simply being.