Nielsen is the usability guru. The lesson is you must master your inbox or it gets hard to do any work at your pc without being worried if there is something critical in your email that you have forgotten about. It is a common reality of our current environment that we are all overwhelmed by inputs and demands.
Take control. Inbox zero today.
Website usability exists in a favorable environment, as users increasingly understand the predominant design conventions and continue to get better connectivity and larger screens. In contrast, email lives in an ever-more hostile environment — that is, in an ever-more crowded inbox. Users in our research were overwhelmed by their inboxes and increasingly felt pressured by unsolicited or fraudulent email.