Paul Hersford Recently Began Teaching His Tenth 2-Hour Wine-Tasting Seminar

Paul Hersford recently began teaching his tenth 2-hour wine-tasting seminar in the banquet hall of a restaurant that has a large and varied wine cellar. His class participants are complaining the class he is teaching is not what they expected. Some are leaving after the first hour without a word to Hersford. No participant has ever taken another one of Hersford's classes even though each class studies a different variety of wine. Which provider gap is causing Hersford the most difficulty? List some possible strategies Hersford can use to close or possibly eliminate this provider gap.