Better late than never means that it is better to do something late than to never do it at all.
Example: "The movie has already started. Do you still want to go in?" Reply: "Sure. Better late than never!"
Better late than never is often used as a polite way to respond when a person says "sorry" for being late.
Example: "Sorry I was late for the meeting today. I got stuck in traffic." Reply: "That's okay. Better late than never."
Better late than never means that even if you are going to be late, you should still go ahead and do the thing, because it is better to do it late than to never do it at all.
Example: "I'm sorry it has taken me so long to return this book." Reply: "Better late than never."
