HTML img tag alt property

I used to slavishly fill in the alt property (as in <img alt="">) to describe every image on my website.

But I recently made a little page for my first entry into the needle felting craft and I left all of the "alts" blank for the first time ever. The property is there, but it’s an empty string.

My new understanding (and it seems perfectly logical) is that if not seeing the image doesn’t deprive the reader of any additional context, it doesn’t need to be redundantly described. And, in fact, it’s annoying to people with screen readers.