@Platt0 It depends on whether you are responding to an Inquiry or a Reservation Request.
With an Inquiry a guest is not required to accept a Special Offer. Since guests can send multiple Inquiries to hosts, they may get several Pre-Approvals and /or Special Offers from which to choose. Once they choose the one that suits them, the guest is not required to respond to the other hosts. Some do, out of courtesy, but it isn't required.
With a Reservation Request, however, it is a different matter. When a guest submits a Reservation Request, Airbnb places an authorization hold on the guest's payment method for the amount of the reservation. Since this hold cannot be held indefinitely, Airbnb requires that the host Accept or Decline within 24 hours. I know many guests, out of not knowing how Airbnb works, ask questions in Reservation Requests and there is a back and forth between the host and guest that can last a long time, especially if they are in different time zones. It is important that the host watch the clock and if the Reservation Request gets close to expiring, decline the request with a polite note that the guest can continue the conversation by clicking on the Contact Host link. Many hosts don't understand how this works and they get into trouble especially since Airbnb blocks the requested dates on the host's calender if the Reservation Request expires. That's why Airbnb sends reminder notices to Accept or Decline.
You can read more about this in the Community Help Guides under Reservation Requests and Inquiries, What's the Difference?
I hope this helps!
