I hope no one's going to shoot me for starting this blasphemous topic.
So, here on this forum we all love Les Mis dearly and agree that it's one of the best novels ever written. But have you heard of or got any criticism of Les Mis? It could be about any aspect of the work.
For example, one of the most common criticisms I've heard is the stereotypical, misogynistic portrayal of women. The well developed characters in Les Mis are all men. They have a complicated backstory and a strong personality. Even minor characters who get probably like five lines in total *cough* Les Amis *cough*
are attractive enough to provoke lengthy discussions. But most women in Les Mis are just there to prove a point. Fantine and Éponine are there to show the suffering of the people. Cosette, after adopted by Valjean, becomes more like a symbol embodying everything perfect than an actual person. Their character development always revolves around romance. Even for Cosette, who gets most screen time of all the women, her development is only limited to a sequence of "growing up, knowing how to dress herself, becoming pretty and finding the love of her life".
I'm sure there's more than that. Feel free to add yours.