When reading the sentence
Die Tickets waren innerhalb einer Woche ausverkauft
i.e. The tickets were sold out in a week
I realised waren is the third person plural preterite (past) conjugation of "sein" so I thought the sentence structure was active i.e. the tickets were doing the action.
I then thought, surely the tickets would receive the action of being sold out since they didn't sell themselves (someone else acted upon them - purchased them) and hence I thought:
Why isn't the sentence above written in a passive tense?
i.e. why don't we use the verb werden with the "ausverkaufen"?
so for example
Die Tickets werden innerhalb einer Woche ausverkauft