And you have no clue.
Most customers never complain. They’re too busy, it’s too awkward, or they just don’t care. Instead, they leave and never come back.
You need to make it as easy as possible for a customer to tell you when something is wrong. An anonymous form, a help@ email address, a Twitter account, or something like this clever switch in a restaurant restroom.
(Thanks, Cale. Glad to know I’m not the only one taking pictures in restrooms.)