[TimPC]

Inbox-zero isn't so much zealotry as a method of managing to-do lists. In the business use case, there seems to be a tipping point where the alternative is that other people are responsible for things they send you, which you might drop because they get buried into your 10,000 other e-mails and by the time you get to them, you might miss some. If you're in a culture where task assignment can happen through e-mail you're almost forced into some variant of inbox zero -- particularly if people aren't going to be following up to check on your progress on small tasks until they expect them to be done at the next meeting.