Why is the grave yard the richest place on earth?

Les Brown, a motivational speaker, once said, " The graveyard is the richest place on earth, because it is here that you will find all the hopes and dreams that were never fulfilled, the books that were never written, the songs that were never sung, the inventions that were never shared, the cures that were never discovered. All because someone was too afraid to take that first step, keep with the problem, or determined to carry out their dream."