How critical are fans allowed to be?

Genuine question.

I appreciate that fans have their opinions, and sometimes they do get worried or unhappy with the way their team is performing. And when it comes to that, then yes, they are entitled to voice their opinions in a respectful manner. There's a difference between voicing criticisms and whining. And there's a difference between saying you don't like something, and just being flat out disrespectful.

But I feel like there has to be a limit to how much you can criticise before you've gone too far. When it comes to the point where you are actually hoping and begging for a manager to get fired and you are calling him insulting nicknames, then I don't see how, if that manager goes and wins a trophy at the end of the season, you can turn around and celebrate without at least holding your hands up and apologising first and admitting you were wrong. I expect and hope the fans who are criticising Mourinho now will, at the end of the season if Mourinho wins a trophy, be willing to eat humble pie and apologise about the way they have spoken about Mourinho. I don't expect a huge gesture, just "I'm happy we won this trophy, I have to hold my hands up and admit I was wrong about Mourinho." Just something like that.

It's like, for example, if you have parents who treat their kid like shiiit. They insult and degrade this kid all the time, they physically abuse the child, they don't invest a penny in that child's education... and that child then goes on to become a huge success in some area, and those parents then turn around and try to take credit and act as if they were supporting this child all the way. Uh... no you guys weren't, the kid became a success despite you, not because of you. You lost all right to claim any credit for what your child achieved when you abused him.

When you insult and disrespect your manager by calling him Boreinho or whatever the furrrk nicknames you want to use and you cross the line by saying you want him to be fired, you forfeit all right to celebrate any trophies or victories Man Utd achieve while Mourinho is in charge. You're allowed to voice criticisms. You're allowed to ask for more from the team or the manager. But you're not allowed to disrespect and insult the manager. That's crossing the line. And if Mourinho is successful this season, I believe the fans that have disrespected him need to eat humble pie and apologise before they can celebrate any success that Mourinho brings their club.