The image above is a great example how to communicate to your customers when you have to ask the customer to do something that’s not in their interest. You position the message so that it’s actually a compliment instead of apologising for the task. Don’t concentrate on yourself and what you’re doing - focus on the customer, they’re giving you their attention. Give something back to them.
The message is from twitter, when they were going through my Gmail contacts whether any of them had an account with twitter.