Last minute deals any good?

What is the catch about the last minute deals? Have you ever thought about this? How come they give so cheap offers and how does this pay off to them? Is it a good option and what do you think its advances and its flaws are? Any thoughts from you, guys?

Sure it pays off for them! Sure it does! If they don't make the price so low, they wouldn't sell those trip package to anyone, would they, now? The only catch, as I see it, is for the people (like me) who require visa to travel to any country of the world, so last minute deals are still just a dream for me.