@Andrea773 Yes, Airbnb could do a better job in explaining how the Security Deposit works....I agree with you. Airbnb does not place an authorization hold on the guest's payment method. Why? Because authorization holds have a limited shelf life and cannot be in force for long periods of time (likely not longer than 24 hours). Some payment methods do not have authorzation hold processing.
That said, Airbnb does have the payment method on file so that if a damage claim is agreed to by the host and guest, Airbnb will charge it.
I recently had an occasion to file a damage claim (first time ever!) and the guest agreed to pay since she was fully aware that her husband caused the damage. Despite agreeing to the claim (which I filed through the Resolution Center) she failed to pay. After waiting for at least 5 business days for the payment to reach my account, I contacted Airbnb about it and they took over. A service rep continuously followed up with my guest until she paid up. It took about 2 weeks for the money to get to me. I was really surprised (and pleased) at how relentless the CS rep was in getting my reimbursement. He sent me progress reports (!).
When I filed the claim, I did it by the book: photos of the damage, original purchase receipt and receipt for the replacing the item. (I save every receipt for items bought for my listing so I can deduct from my taxes.)
Airbnb does have a process for mediation in the event that a host and guest have a disagreement about whether the guest damaged something and / or the cost of the repair / replacement. In these cases, a case manager will evaluate all the available information including messages between host and guest, and host / guest prior track record on Airbnb. Keep in mind, guests are not held liable for general wear and tear situations and likely won't honor a damage claim if the item was in disrepair to begin with.
My sense is that so long as a damage claim is reasonable and the host files a claim promptly and according to instructions, Airbnb will do its best to collect on behalf of the host. Is it 100% guaranteed that a host will receive compensation? No.
All that said, I do have my own personal short term rental insurance that covers damage in the event Airbnb cannot collect on a claim. And, Airbnb encourages hosts to have their own insurance as well.
I hope this helps!