Life is like a Pencil

I was browsing the World Wide Web for some bounty hunter metal detectors when I suddenly saw this very interesting phrase about life.

Here it is:

“3 lessons to be learn from a pencil: Everything you do leaves a mark. Pain always sharpen you. What's inside you is useful, not what's outside. “

Every word of it really touches me personally, I am just hoping that in time I would realized it fully and understand every bit of it.