Most of the bloggers that we have today are in blogging due to money itself. Yeah, it’s like the new gold rush (since 2005 anyway). It’s the optimism that hard work does pays off by writing good contents, and slipping in a few Adsense ads here and there will get them some clicks and thus revenue.
Just as a reminder for all those who think that this is easy. If you’re using Adsense only to monetize your site, then traffic is what you need MOST. And without content, there won’t be any traffic. Keep in mind also that not every niche (industry) pays the same per click. Making an assumption that blogging about gaming and mp3 players will get you higher per click revenue compared to the insurance industry will just make your life miserable since that will never ever happen.
Adsense doesn’t provide the highest yield in terms of revenue. Besides Adsense, you can also try to sell your own ads or promote affiliate offers where you can then earn affiliate commissions.