Managers vs Makers
TL;DR
Developers (Makers) and Managers work differently.
- Makers plan in half-day blocks of time. These are developers.
- Managers plan to minimize empty 15-minute slots in their calendar.
Interrupts are costly for developers and therefore the business.
http://www.paulgraham.com/makersschedule.html
(Paul Graham - YCombinator Founder)