For me blogging is something that I like, I could do it for a long time without even having a return from it. But, I truly believe that if you put a lot of efforts to something, make something useful for others, you must receive a profit out of it. First of all it motivates you not to give up and secondly it inspires you to make your work better.
First of all, I decided to start blogging when I found out that I want to share. We used to be consumers, and rarely givers. I think it is like to give a present. Some people like more giving presents, while others want only to receive them. I am sure we should live in balance and do not forget about sharing. If you are knowledgeable of something, do not be afraid of sharing your knowledge and experience to others. As such it always makes you wiser.