1. 99% of the traffic never returns
2. The useless traffic crashes your server
3. Most users are fickle teens
4. Interesting comments are buried when they go against others opinions
5. The vast majority of comments are poor attempts at comical one liners
6. Political posts receive bias feedback
7. Famously if you’re not a friend of the top diggers you’ll rarely get anywhere
8. If you’re not writing about Ubuntu, Linux or Apple you’ll find it much harder to become popular
9. Misleading titles to encourage clicks
10. No community should ever have 100% freedom to do and say as they please

None of the list is true all of the time, just the vast majority. This is not a bitter post, some of Digg is excellent but it’s been downhill for quite a while in my opinion.