This is a question that all of us bloggers seem to obsess with. None of us can clearly state why, except those that have monetized their blogs and are very clear that they blog to make money and hope for the day when they can do it full time and get away from the rat race.
But, the more I read the blogs of the latter type, the more I find that they spend more time blogging and making money than if they had been doing it as a pleasurable activity. They seem to have got on to a tread mill from which, they are unable to get off.
In my quest to find the answer to the question, I have been surfing the net and I came across a very nice blog which throws very interesting light on this subject. Coming from a medical source, I find it fascinating.
I hope that you will find it as interesting and illuminating as I did.