MANAGEMENT VISIT

"He can't tell a X from a hole in the ground" is a common phrase that indicates that someone is the opposite of being an expert.

A hole in the ground is a very commonplace thing. It would be possible to change the phrase by saying, e.g. "He can't tell a good piece of furniture from a cardboard box." 
However most people simply use the traditional version.


IT'S BEEN ONE OF THOSE DAYS!