at the end of the semester or the end of the school year?

你们寝室卫生怎么样
So I'm just guessing, having been in a few of these things over the years,

我看啊因为我也念过大学
that by the end of the semester, or certainly by the end of the school year,

期末或年末的时候
the state of the average Yale dorm room is quite disgusting.

耶鲁大学多数寝室会挺恶心的
Why is it disgusting? It's disgusting because people don't tidy up.

为什么会很恶心啊因为没人打扫啊
They don't clean up those bits of pizza

谁都不愿意清理吃剩的比萨
and bits of chewed bread and cheese.

奶酪渣还有面包渣
But why don't they tidy up? Well let's just work it out.

为什么你们不打扫啊我们来分析一下
What would you like to happen if you're sharing a dorm room?

到底有什么问题
You'd like to have the other guy tidy up, right?

你们指望别人去打扫卫生对不对
The best thing for you is to have the other guy tidy up

让别人去打扫卫生是你最希望的结果
and the worst thing for you is to tidy up for the other guy.

你为大家打扫卫生是你最不希望的结果