When you purchase a ticket from them and resell it on their marketplace, once someone purchases it, they(Ticketmaster) hold your funds and only give you the money ~7-14 business days after the event is over. They say this is to verify the validity of the ticket.
On the buyer side, you purchase the ticket from the marketplace and it gets added to your account immediately. (I think) You get the barcode some time ~1 week before the actual event begins.
The confusion for me? Ticketmaster owned the ticket and all logic relating to the validity of it. The logic to validate this shouldn't be complex at all. They OWN the ticket. They KNOW it's legitimate because it never left their database. Yet they double dip and hold both buyer and seller funds. Events can be close to a year in the future but the seller won't see that until after that event ends.