If an event sells out, a Waitlist will automatically be generated. Fans can pre-authorize their credit cards for an order of tickets and orders are immediately fulfilled if more inventory becomes available. Waitlist can also be used as a type of crowdfunding for events. As artists or event organizers try to gauge demand, fans can demand that event by pre-authorizing an order to purchase tickets, in hopes it will indeed take place.
With Waitlist, fans now have a chance to score tickets to their favorite events that sell out, without having to continuously check back for available tickets and without being forced to buy through second parties. Fans also now have the opportunity to demand events they would like to attend. Event organizers now have the ability to guarantee sales to deserving fans when increasing inventory, and can precisely gauge demand for future events.
That's the gist of it!