Asking for a customer reference is tricky. It's awkward for most people-after all, you're asking somebody who already pays you money to go out of their way for something you need. People assume that customers don't want to be references, so they treat them that way: delicately, cautiously, nervously.
If you are doing this (or if you're not asking at all) you've got it all wrong. Here's our advice for successfully asking for a customer reference.