[spicymapotofu]

People who want a deeper understanding of the related fields do read these. Furthermore, to reiterate the GP's reaction to GGP's sentiment about few reading them, their readership or lack thereof is not a variable in the question of their value. We can speak to many technical guides that would increase people's productivity if they only read them.

Popularity is more a question of marketability, especially in the dire non-fiction category. Reading is a secondary use for most of these books, and it makes it even harder to discern which lifestyle books are resume-padding filler or truly generalizable advice.