What I think is missed by most scholars here about Guan Yu is that he was a clear, large target for everyone of 3k times.
Most of you will quickly dismiss him as an idiot, or arrogant or a million other things before you would say he was a target.
You see. The way I see it is this:
Many other generals who had a lot of balls at the time got defeated, we dont look down on them for that. This includes people like Pang De, who was clearly a pretty good general, but was defeated.
Many other generals also had reputation which they did not fulfill. People like Ma Su, though looked at now as a bit of a fool isn't quite as berated as Guan Yu.
That's because Guan Yu had the reputation, even in 3k times to be invincible and powerful as a man and a warrior. He was seen as a really important figure for Shu and Liu Bei, and an amazing man in general.
So was it such a surprise when Guan Yu, who was clearly just a strong and confident man, should be beaten?.
If Guan Yu never had that reputation in the first place, we'd all probably either not be so up tight about him, or we'd probably just dismiss his failure as a misfortune which should have been expected, or one which he could not do much about, seeing as he was a normal warrior and man.
Because he had this reputation, he became a 3k target which Wu and Wei both wanted to knock down. So Guan Yu's defeat was inevitable because of these factors. Nobody could have resisted at Jing, regardless of their abilities, so maybe we should give him a break? After all, he was just a man.