In no particular order:
- Writing for Twitter clicks instead of a real audience.
- Bad design/no variation in layout
- Lazy writing: little thought, very little research, no editing.
- Writing for SEO keywords.
- Short posts about the same thing we’ve read 1,000 times before with no depth.
- Being too informal and/or biased, i.e. not sounding the least bit objective.
- Being to formal and uptight, i.e. sounding like a corporate megalopoly.
- Inconsistency: not posting regularly.
- Not knowing what one is talking about but talking anyway, a.k.a. ignorance.
- Rampant use of top-10 lists
- Bonus (edit): Not allowing comments. (Thanks, @thetylerhayes)
I have been guilty of all of these at least once. I’m working on it. :)