Dorin BOERESCU had the following PPT:
at his presentation at GPEC.
The main idea?
If you are an online store, you should make an effort to provide online customer support for more than 9-17; strive to have someone online to answer request after 17:00; see the above graph for the reason behind this.
Note: Also see the Yahoo! Group on which I present similar issues: IMRo. To join, email firstname.lastname@example.org and reply to the confirmation email.