With all due respect to J.R.R. Tolkien and other authors who have labored long and hard for their books, I hate fictional languages in books.
This may be an unpopular opinion but the sight of a lot of writing in made up languages makes me want to put the book down.
I hate trying to figure out how they want their words pronounced. There don’t tend to be any guides so you know that you are probably guessing wrong. I also don’t want to work that hard on that aspect of reading.
Names, especially in high fantasy, can be the absolute worst. Why does there have to be so many apostrophes? More than one in a name is absolutely too many. Most made up names could generally be helped by halving the number of letters and by substituting a few vowels for some of the remaining letters. My brain doesn’t know how to say Fr’ythx’thsz and is going to short circuit if I make it try. My mental voice will just skip right over it when reading. If there a Fr’yshcx’frsz to go along with Fr’ythx’thsz I’ll never be able to tell the characters apart and I’m done with this book. I will be salty about it.
This may be one of the reasons that I don’t read a lot of epic fantasy. I look at the names in the synopsis and put the book right down. Why can’t characters be named Bee or Ock or Luis? So much easier.
Is it just me? Do other people like to read long poems in made up languages in the middle of a book? Mostly I just think, “Wow, you worked really hard on that,” and then skip right over it to wherever the action picks up again.