I might just be too picky about giving out the superlatives.
There are plenty of books that make my spirit soar, or draw me in to a legendary feeling or world, or where the characters feel like family. And then they'll have one thing I don't like or not stick the ending, or I read a paragraph by someone like Josephine Tey at her best and be reminded how their wordsmithing isn't that.
I guess I could start using great for things I'd give an 8/10 instead of 10/10. Maybe easier to just not worry about it.