Am I the only one who doesn't find this funny?

"I used to be an adventurer like you, but then I took an arrow to the knee."

So, I've played plenty of Skyrim, and I'm pretty sure I've heard that said by the guards, but now all of the sudden it's a widespread internet joke.

... what?

I honestly fail to see what is so mind-numbingly hilarious about this quote. Please, someone explain it to me.