Many people dislike Ronda Rousey because she made MMA much more popular than it already was. Upon her arrival to the UFC, it was a huge deal considering how Dana White, the president of the UFC, said that women will never fight in the UFC before.
One of the reasons why so many UFC hate Ronda Rousey is because she's a female and there is a group of fans that believe women cannot fight.
Color commentators like Joe Rogan and UFC staff in general would always hype-up Ronda Rousey, not only as a fighter but as a person. People dislike others who may seem perfect or may be called perfect by others. This triggered a lot of people to hate her.
Ronda Rousey has had one of the best MMA female fighter careers with plenty of first-round wins and only a one loss. The routine in her wins made people grow bored of her winning and wanted to see her lose
Despite of the hype, Ronda Rousey was on the receiving end of a beating to then "no-one" Holly Holm. This made people lose their love to Rousey and decided that she is not as good as the UFC made her seem to be.
There were several ocassions where Ronda would seem like a very disrespectful person especially in weigh-ins and at the beginning of her matches.
Ronda Rousey's appearance changed to the fans who follow TUF. She was a very mean and rude person and her behaviour turned a lot of people against her in favor of Miesha Tate. However, Rousey beat Tate for the second time then.
There were a lot of ocassions where Rousey seemed like an outrageous person. Several fighters have had moments with Rousey that made the news such as Paige Vanzant's talk after losing to Holly Holm. Paige Vanzant claims that Rousey got mad at her for congratulatin Holm.
Travis Brown is one of the most hated UFC heavyweights because he did not reach his potential, his loss-record and the fact that he keeps getting top-notch names for his fights despite his lack of skill.
As soon as Rousey lost, she disappeared from the public image and spent months without saying a word on the news or through social networks. This made people think that she decided to disappear as soon as she's lost despite telling media that she will take time off after her match with Holm.
One of Rousey's signature moves is glaring into her opponent to be more intimidating before her fight. This has led people outright to hate her because of her apparent intimidation. People don't like those who are intimidating, especially when their opponents are respectful.
Rousey never shakes her opponent's hand at the weigh-ins. She doesn't do anything but rush into them then leave or trash-talk them. A lot of people hate that about her.
Rousey has had numerous feuds with fighters like Miesha Tate, Beth Corriea and Holly Holm among others have led fans to believe that it is Rousey who is sparking the hatred.
Rousey has claimed several times that she is the best and that no one will beat her. People grew sick of her attitute and the ego she continuously shows.
Rousey has said in her book that she has beaten up her boyfriend then. This is domestic abuse that a lot of people stand against.
Despite having beaten up her ex boyfriend, Rousey has took verbal jabs at Floyd Mayweather for his domestic abuse. The verbal feud between the two has taken several turns and people became divided between who they should hate more which resulted in more hatred for Rousey eventually.
Despite her reputation as the "baddest woman on the planet", Ronda Rousey has shown many holes in her stand-up game especially against Holly Holm. While people usually like winners in the sport, her holes were too obvious even before the Holm fight that a lot of people knew it was all her ego.