It had an alternative world. Great. There were loads of characters, all with new, unmemorable names so the reader has no mental peg to hang them on. Not so great. It was populated by some sentient, talking animals. Fine. But if you define your animals as being like pigs, then call them noggletrugs you've added another word for the poor reader to remember.
There has to be a danger, a journey or quest, some fights - all the usual things. But the reader struggling to remember who's who will very soon forget the whys and wherefores. I literally lost the plot while trying to remember all the names of the characters and their relationship to one another. I couldn't remember who was going where and why. I didn't care why the noggletrugs were fighting with the… for flip's sake, if they’re like goats, call them goats! I stopped reading.
Tolkien had lots of characters in LOTR but he'd introduced some of them in The Hobbit and eased us in gently. He called his trees trees but the tree-herders were Ents. In giving the Ents characters, a story, a part in the plot, he made them memorable. But he called his horses horses and his eagles eagles. We were in with a shout.
I know that Mozart’s patron was supposedly showing his ignorance of the musical style when complaining that there were too many notes, but I find myself thinking there are too many names in some books. I feel that if the character isn’t important enough for us to get to know him/her so that the name has a meaning and not merely a sound, then that character probably doesn’t need to be there.
At the risk of appearing a philistine, like Emperor Joseph II, I have to say, ‘Too many names, Mr Author!’