If not, have you ever thought about doing so? Why, or why not?
No I don't review books for anyone. Why not? I don't want to have to tied down to a certain book to read, and then have to write a review about it. It takes me back to my high school days, when we were required to read a certain amount of books and then write a book report, (as they were called in my day!) I prefer to read at my own pace, and not be on a schedule of having to read a certain number of books to keep up with the book reviews. I really don't have the time to read more than one book a week, sometimes I manage two.
Do I write book reviews, yes sometimes I do, but who for? Myself. I don't think I would be fair to the author or the publisher, if I were provided the book to write a review about. Since I do it for myself, I can say whatever I choose. If I like a book I will say so, likewise, if I hate a book I will say so.
Why do I think that would not be fair to the author/publisher. For an example: This past week, the book I was reading was OK, I would give it 2 1/2 stars, out of 5. For some reason it just couldn't hold my attention for very long. So to get the book read I would say each day to myself, I am going to read 100 pages today, or 50 pages today. It took me about a week and a half to get that book read, I finished it this weekend. Now, I don't blame the author for this, because it may have been my own fault. However, would I recommend that book to someone else to read? NO. But, as I read other reviews of the book, it seems some enjoyed the book, whereas, there were others who like me just didn't care for it at all.
I also enjoy choosing the books I want to read, so I buy them or get them from my library. I just like to read for my own enjoyment, with no strings attached.