Do you normally spend at least 15 minutes a day commenting on other blogs? Why or why not?

I do leave comments sometimes but not as much as I probably should.

What are some reasons you DON’T comment on an entry you otherwise would have? (For example, a registration process deters me from commenting.)

Sometimes blogs want to much info and I don’t want to fill it all out. Sometimes I do not have time and sometimes I will enter everything and then that Captcha thing messes it all up and then I give up.