health, your friends, your favorite passions – things that if
everything else was lost and only they remained, your life would still
be full. The BBs are the other things
that matter, like your job, your house, your car. The sand is everything
else – the small stuff.
If you put the sand into the jar first, there is no room for the BBs or the marbles, the same goes for life. If you spend all your time and energy on the small stuff, you will never have room for the things that are important to you.