Who am I blogging for?

From one of my favorite writing books:

You are writing primarily to please yourself, and if you go about it with enjoyment you will also entertain the readers who are worth writing for. If you lose the dullards back in the dust, you don’t want them anyway.

William Zinsser: Chapter 5, On Writing Well —The Audience

(From the Oxford English Dictionary: Dullard: A dull or stupid person; a dolt, dunce.)