1. People generally try to figure out how to make the most money (benefit) for the least effort (cost).

2. In the case of authors, that has a huge overlap with selling a lot on Amazon. Thus, figuring out how to use Amazon sales/marketing algorithms, is useful.

3. Amazon (or other sellers) can always change things on their end to pursue their goals, monetary-related or otherwise.

4. Thus, figuring out algorithms at one point may not work later.

5. Readers matter: reading habits in one genre may not cross to other genres.

6. Romance skews everything. You find romance mislabeled everywhere, especially sci-fi and fantasy, because sci-fi and fantasy are more setting types than genre types.

7. This matters most if you're writing for money and/or fame, not for the muse.

8. What's the point? No clue. I'm just trying to understand where things are now, not point the way ahead.