You should consider using not only mystery shoppers, but also quarterly focus groups made up of some of the store's actual customers. (petbusiness.com)
I believe this is only a mystery because so many have not considered the complexity of the forms and applications of said communication. (redeeminggod.com)
> It's one of the great mysteries It's only a mystery if you don't want to spend some of your time learning about science and facts. (religion.blogs.cnn.com)