I have a very important reason to tell you about why you should choose paid hosting instead of free Web Hosting for your lovely Blog or precious Website. That one very important reason for going to paid hosting is that many companies block blogging platforms. In my company, Blogspot.com and wordpress.com both are blocked with many social networking websites. In that case if your important blog is in blogspot.com or wordpress.com then no one from our company can visit your Blog. Yes, you can say it is our loss as well that we cannot visit your important Blog.
When you write your blog or take care of your Website with all important and useful contents in it then you wish to increase visitors so that message can reach to all people on the internet who need your service.
There are many reasons cited not to opt for Free Hosting but the one I understand is most important as this directly deny your probable users access to your webpage.
Here is how the page of this Blog looks from within my company:
I could access the page from Company as I am using custom domain and not *.blogspot.com but because Image is hosted on blogspot.com and Facebook and Twitter etc are blocking hence blackout (whiteout) on sidebar.
Another big reason given for not choosing Free hosting is that it make your blog one among all. But this problem you can solve by using custom Domain!