1. It managed to run for ten seasons without getting boring.
2. It had non-stop funniness in every episode.
3. When the last episode ended u wanted to cry.
4. u feel like you're one of them.
5. They're not always predictable, unlike some other shows.
6. There's so many different ideas.
7. Their chemistry is GREAT.
8. u think you're going to die laughing at it.
9. u don't care how many times you've already seen each episode.
10. It can be extremely like real life.

This is only ten I can think of many more...