" Another benefit of a sender filter is that it resets expectations. The most crucial line in my description is the following: “I’ll only respond to those proposals that are a good match for my schedule and interests.” This seems minor, but it makes a substantial difference in how my correspondents think about their messages to me. The default social convention surrounding e-mail is that unless you’re famous, if someone sends you something, you owe him or her a response. For most, therefore, an inbox full of messages generates a major sense of obligation. By instead resetting your correspondents’ expectations to the reality that you’ll probably not respond, the experience is transformed. The inbox is now a collection of opportunities that you can glance at when you have the free time—seeking out those that make sense for you to engage. But the pile of unread messages no longer generates a sense of obligation. You could, if you wanted to, ignore them all, and nothing bad would happen. Psychologically, this can be freeing. "

― Cal Newport , Deep Work: Rules for Focused Success in a Distracted World