Do you always need to disemble a clarinet?

If it is for display only, I'm pretty sure the cork won't deteriorate. The reason behind disembling a clarinet is for easy cleaning, and easy portability. If you are constantly putting the clarinet together and taking it apart and use cork grease liberally, then the cork will deteriorate. I'm sure it's not terrible for the instrument, but that is considering you won't ever be playing it and it is for display only. I hope that helped.