SIN #5: Being inaccessible when needed. If customers are important to you, you’ll answer their email or voice mail within minutes, not hours.
I recently attempted to contact 20 people I had met, granted I was not YET a customer, but in every case I heard the standard voice mail message that sounded so bored and uninteresting. I left an enthusiastic message and of the 20 only 3 called me back. It is now 2 business days later. They do not know what I wanted but if I wanted to buy, they lost the order!.
This further supports the next part of this Sin:
Not communicating as they wish to be communicated with. Not encouraging phone communication to avoid misunderstandings.