Other mistake: As the surviving characters discuss the fate of Westeros, 2 plastic water bottles can be seen tucked behind the chairs they're sitting on.
The Last Of The Starks - S8-E4
Other mistake: During the scene in the banquet hall, as Tormund says "most people get bloody murdered, they stay that way", look at Daenerys in the background - a disposable coffee cup is on the table in front of her. This brown cup with a white plastic lid is nothing remotely like the style of cups they're all drinking from in the scene. HBO acknowledged the slip up and digitally edited it out on streaming services, reruns and future DVD releases.
Tyrion: I heard there was some trouble in Littlefinger's brothel the other night.
Janos Slynt: Mmhmm. Nasty business, had to be done.
Tyrion: Yes, of course. The City Watch must keep the peace. Only, I hadn't realised peace depended on killing babies.
Janos Slynt: Orders are orders.
Tyrion: Quite right. Especially the Queen's orders.
Janos Slynt: I never said they were the Queen's orders.
Tyrion: No, but who else would want to murder King Robert's bastards? She's always been a jealous woman.
Janos Slynt: You know your sister better than I do.
Tyrion: You've heard the awful rumors about my brother and sister.
Janos Slynt: I don't listen to filth.
Tyrion: That's good of you, but you have heard them. I suppose people who do believe that filth consider Robert's bastards to be better claimants to the throne than Cersei's children.
Janos Slynt: Joffrey is my king, the rest doesn't interest me.
Tyrion: I appreciate your loyalty. Tell me, when your men slaughtered Ned Stark's men in the Throne Room, did you give the order?
Janos Slynt: I did, and I would again. The man was a traitor. He tried to buy my loyalty.
Tyrion: The fool. He had no idea you were already bought.
Janos Slynt: Are you drunk!? I'll not have my honor questioned by an imp!
Tyrion: I'm not questioning your honor, Lord Janos. I'm denying its existence.
Janos Slynt: If you think I'll stand here and take this from you, dwarf...
Tyrion: "Dwarf." Hmm, you should've stopped at imp. And yes, you will stand here and take it from me. Unless you'd like to take it from my friend here [motions to Bronn]. I intend to serve as Hand of the King until my father returns from the war, and seeing as you betrayed the last Hand of the King, well I just wouldn't feel safe with you lurking about.
Blackfish: Kingslayer.
Jaime: Blackfish.
Blackfish: I assume you're here to fulfill the vow you gave my niece. I don't see Sansa and Arya.
Jaime: I don't have them.
Blackfish: Pity. Do you wish to resume your captivity? [Jaime shakes his head "no."] Then why are you here?
Jaime: You know why I'm here. This castle belongs to House Frey. You're trespassing. In the name of King Tommen, I order you to surrender, or...
Blackfish: Or you'll kill Edmure. My nephew's marked for death no matter what. Hang him and be done with it.
Jaime: It won't stop with Edmure. You'll force me to storm the castle. Hundreds will die.
Blackfish: Hundreds of mine. Thousands of yours. If you can breach the walls.
Jaime: We'll breach them, and kill every last one of you. But if you surrender, I'll spare the lives of your men, on my honor.
Blackfish: Your "honor." Bargaining with oath-breakers is like building on quicksand.
Jaime: The war is over, Ser. Why sacrifice living men to a lost cause?
Blackfish: As long as I'm standing, the war is not over. This is my home. I was born in this castle, and I'm ready to die in it. So you can either attack, or try to starve us out. We have enough provisions for two years. Do you have two years, Kingslayer?
Jaime: You clearly have no intention of saving your men's lives. Why did you come treat with me?
Blackfish: Sieges are dull, and I wanted to see you in person, get the measure of you.
Jaime: Well now you have.
Blackfish: Aye, now I have. I'm disappointed.
Trivia: One of the severed heads on a spike is that of former president George W. Bush. Before shooting the scene, George RR Martin asked writers and producers David Benioff and D.B.Weis to have a cast of their 3 heads to be put on the spikes, but for budget reasons they opted to get a box from HBO's warehouse with used severed heads. They noted that one was Bush's, but they put a wig on it and got away with nobody noticing. In the Blu-Ray commentary the producers revealed the story, and got a lot of criticism from the right.
Answer: Basically it's because he broke his vow. A member of the Kingsguard is sworn to protect the king at all costs. Jaime elaborates more on the deed to both Catelyn Stark and Brienne of Tarth, telling Catelyn that no matter what course of action he took, he would be breaking one vow or another (i.e. if he obeyed the king, he would conversely be disobeying his own father), and telling Brienne that the Mad King was planning on burning all of King's Landing, but he did not bother to tell Ned Stark that. Ned Stark felt that killing Aerys was dishonorable and excessive. Robert Baratheon still could have usurped the throne without Aerys being killed.
Phaneron ★