three most important 'L' in the world

Laugh, Love, Life...
I just realize that the three things keeping human intact,
keeping them in sanity.
these three things, they are connected one to another,
and without one the others will crumble and fall.
Laugh keeps life and love colorful, not monotonous like.
No matter how successful the person could be, without the two others it'll worth nothing.
But then why do the mankind always neglect these three?
As if they are some kind of old toys that you don't use anymore and placed on the back shelf.
But also like old toys, they will always be there and cheer us up when we need them.