When I was young my grandparents had literally 100's of Readers Digest books, each of which contained several books in condensed form.
I was a bit disappointed when I found out that condensed meant I was not getting the whole book, but up to the time I enjoyed them. I was pretty around thirteen when I read a book the I had previously read in Readers Digest book and I found it a lot better.
Still many people liked the Readers Digest books because they were condensed.
Even today, I might go for the smaller Bio after Wikipedia, and then get something more in depth if I was still interested. An example would be Rex Stout who kind of fascinates me from reading short book inserts, but I am not interested enough to pay $110 for a biography. And stupid of me I know, because even if I bought a second hand copy for under $5.00 a $110 book intimidates me. (perhaps I should look for a library copy
Helen