That is a big "if" though. A lot of blogs don't try to be businesses. Personally, I use my personal blog to write about things I'm interested in writing about whether it's hobby-related stuff or technology. About a year ago I was thinking about starting a separate travel and food blog I was going to be more serious about and quickly realized I really couldn't be bothered.
If you're going to run a blog as a business, you also probably need to have a clear area of focus and I'm just not interested in doing that. A lot of my tech stuff also ends up running in other places these days where it gets better readership anyway.
For every Daring Fireball, there are 100 blogs neither you nor I have probably heard of that are profitable businesses.
He averages about 5 posts a month, and has months where he writes 1 post:
If you run your blog like a business, as in you have a real need for growth and to turn a profit, you will need to pump out content on a regular basis.