I once had a manager who apologized if he didn’t respond to an instant message within 15 minutes.
While this might seem polite and courteous, it indicated that the manager thought of a 15-minute response to an instant message to be too slow. As his team, we proceeded to respond to his messages the moment they arrived.
Focused work requires long periods of no interruption – periods that are incompatible with responding to every instant message within 15 minutes. The expectation that instant messages need to receive an instant reply destroys the focus necessary for deep work.
Perhaps we need to stop calling it ‘instant messaging’.
Observations 