It's hard to generalize.
From: Doug Allen <dallen@parktudor.org> Date: January 1, 2013, 4:13:28 PM EST To: Doug Allen <dallen@parktudor.org> Subject: Getting started with "Getting Things Done" | 43 Folders
http://www.43folders.com/2004/09/08/getting-started-with-getting-things-done