Oh man, back when I was reading through the Hugo winner list it was a victory parade of awful covers. There's a particular grossness to the 60s-70s era, but it's hard to say there's a time period where they don't suck. The other day I picked up one which has this exceptionally awful cover: It's bad enough that I had to hide the cover of it when leaving the bookstore, but I also have this terrible non-germane representation of the character corrupting my mental image of what the character was intended to be. Edit: OH almost forgot the worst part: red edge gilding on the book.
I think it was a problem of cheapness. There were lots of books, there were talented illustrators, but there wasn't enough money for every book to have a talented illustrator. I mean, that's peak Frank Franzetta time. Michael Whelan was rolling in. Vincent de Fate was everywhere. But you also got stuff like this: (also a Jack Vance, first book of Planet of Adventure, which your Jack Vance cover has also been used for:)
