count是“计算”，count for nothing算一下，什么都不是，说明本身并无任何价值可言；无足轻重；毫无价值；一钱不值；算不了什么。

【例句】
They regarded us as little kids who count for nothing.
他们把我们看作是无足轻重的孩子。

When it comes to money, all the promises he's made to his friends count for nothing.
只要涉及到钱，他对朋友的所有承诺都丝毫没有意义。