Wine glasses are kept in an inverted position because that way they remain cleaner than they would if they were stored upright. A corner wine glass rack also protects your wine glasses while keeping them in easier reach than they would be if they were stored in a cabinet.
Some units permit you to lay bottles on the shelf under which the wine glasses are suspended. A few bottles of wine is the max for some shelves whereas the capacity of other units is so great that they can hold more than a dozen bottles and the. have room for displaying photos or mementos.