I'm guessing it was either Terry Pratchett or someone trying to look like him. It wasn’t Terry Pratchett - although come to think if it, I’m not a Pratchett fan, so that might have influenced me.
I have a dislike of author names which are obviously fanciful. “Morgana Ravenclaw, author of the 200 book series about sexy goblins”, kind of thing. I figure their books are likely to eschew such quotidian considerations as plot.
I get a lot of authors and book suggestions pop up in my FB feed and some of them I click through, but many I don’t. It’s mostly not based on the photo, more on an avoidance of the “you’ll sit up all night reading this book” kind of thing. Or the title with a built-in review. “Murder in the Shrubbery: a laugh-out loud romantic comedy you’ll never forget.” I get irritated at being told how I’m going to feel about a book before I’ve read it.
I also refuse to read a book where the characters have apostrophes in their names, (other than the O’Toole or whatever kind of name). Life’s too short to keep reading, “And then Fn’arion smacked A’phition in the random apostrophe”.
My other criterion is that of blurbs which are badly written. This is more an issue on Amazon where writers seem to write their own blurbs. If someone can’t write 300 words about their own book, which are engaging and literate, the chances if them writing an entire engaging novel seem slender.
Poor writers, doing their best in a marketplace full of picky readers like me. And that’s even before I’ve started the book.