A Forbes post by James Slavet of venture firm Greylock Partners a while back offered five "metrics" to "improve the company at an atomic level." Metric No. 1: Flow state percentage, which he described as “that feeling when you’re ‘in the zone,’ cranking on something.”
Anyone who has IM or email alerts set for every incoming message knows that’s no way to get anything done.
… far too often, this state is broken up by a tap on your shoulder or a phone call. There’s a small, innocent question – and it takes you five minutes to answer it. But when you come back to your original task, the inspiration is gone. The “zone” is gone. You need a half hour to just bring back all the variables back into your mind. Or worse, you may not catch the sense of “flow” again that day at all.
A post at paulgraham.com explained that 3 p.m. meetings can totally disrupt programmers' schedules by cutting the afternoon into two small blocks of time where it’s difficult to get anything done.
Weinstein urges companies to actually measure interruptions for your development team and to set goals for reducing them. He suggests setting up two mailboxes in the issue-tracking system: one for emergencies (say, the site’s down) and one for less-dire issues.
His experience at Wetpaint, at a time when the company was struggling to move the product forward, revealed that morale went up when interruptions were reduced. A key to its success: a rotating triage system with only managers on pager duty. Problems were rooted out and nothing fell through the cracks anymore.