I do not offer my books or courses for free.
The primary reason is that I feel that I give away enough of myself for free already. I have authored 400+ free blog posts and tutorials on the PyImageSearch blog. I have also personally answered over 14,000 comments on the PyImageSearch blog, again, for free.
There is a point where I need to charge for products to help justify my time spent on PyImageSearch and to further help others as well.
I do hope you understand and I hope you continue to enjoy the free tutorials on the PyImageSearch blog.