The only reason that I gave two stars is the staff tries their hardest to deal with the severely understaffed condition.
An average wait time of 20 minutes for customers (observed from personal experience) is unacceptable.
I suspect that the owner of this location may not give a darn about the situation; he or she would otherwise staff the place properly. The understaffing condition is obvious to any customer who enters the location. Pinching pennies, at the price of shortchanging customer service and unnecessarily overburdening your employees, is not a good business modus operandi.
Get a grip, owner. And until you do, I and my friends and family will boycott your place.