What does the idiom hit nail on head mean?

The idiom "hit the nail on the head" means to do or say something exactly right, to perfectly understand or solve a problem, or to make a very accurate observation.

It's often used to praise someone for their accuracy or insight, like:

* "You hit the nail on the head when you said the problem was lack of communication."

* "He hit the nail on the head with his analysis of the market trends."

The idiom originates from the act of hammering a nail straight into wood. If you hit the nail directly on the head, it goes in easily and securely. If you miss, the nail bends or goes in crookedly.