When is blogging a waste of time?

I read an interesting blog post today on 'When is blogging a waste of time'? And it gets me thinking. To me, blogging is a waste of time when:

the server is slow
I have to think too hard on what to write
I have other priorities
I have to fix bugs on the computer
I am unfamiliar with HTML and scripts
I talk crap

Uhh.. what about you? When is blogging a waste of time for you?