Watercooler effect refers to the effect created by two or more employees having an informal, face-to-face conversation, as though at a watercooler. A theory says that people come up with their best ideas when grouped informally.

“饮水机效应”指几个员工在一起进行的非正式的面对面的谈话，就像在饮水机旁的闲聊一样。有理论称，人们在非正式的谈天小组中能想出最好的创意。

Example: 

The president attributed the success to the "watercooler effect" -- employees comparing plans among themselves at work.

董事长将这一成功归功于“饮水机效应”，也就是员工私底下进行方案比较的做法。