"Words you say, never seem to live up to the ones inside your head". These are lyrics to a Soundgarden song I first heard a looooong time ago. I still sing them to myself often.
We hold it all in, don't we?
If your daughter looks pretty, tell her. If you really appreciate the laughter from an unconditional friendship, tell them. If you love someone, tell them.
It may not come out how you rehearsed it in your head, but at least it came out.