The shop
A small shop with a long memory.
For most of our history the work has been unglamorous and useful. Building libraries for schools. Stocking shelves for institutions. Tracking down the one edition a customer actually needed, and holding it behind the counter until they could come back for it.
That is where the judgement comes from. Four generations of watching which books people return to, which ones they lend out and never get back, and which ones simply sit on a shelf looking expensive.