1. Do what they want, when they want. 
2. They rarely listen to you. 
3. They're totally unpredictable. 
4. They whine when they are not happy. 
5. When you want to play they want to be left alone. 
6. When you want to be alone, they want to play. 
7. They expect you to cater to their every whim. 
8. They're moody. 
9. They leave their hair everywhere. 
10. They drive you nuts. 

Conclusion: Cats are little, tiny women in cheap fur coats