mystery shopping
noun /ˌmɪstri ˈʃɒpɪŋ/
/ˌmɪstəri ˈʃɑːpɪŋ/
[uncountable]- the activity of visiting or phoning a shop or other business, or using their website, pretending to be a customer, in order to get information on the quality of the service, the facilities, etc.
- Today, mystery shopping is primarily used by businesses to measure their customer service.