Timeshares can be difficult to sell, and some owners are forced to walk away from their timeshare when they can no longer afford the loan payments and/or maintenance fees. The timeshare lender and/or timeshare resort management company will send out notices when payments are missed. The notices notify the owner of a missed payment and in most countries they are a required first step in reclaiming the timeshare. If enough payments are missed the lender and/or timeshare resort management will proceed with legal action to reclaim the timeshare.
Timeshares reclaimed by timeshare resort management (due to missed maintenance fee payments) are typically listed on the resale market or rented and there is typically no effort to collect additional debt and it will most likely not affect your credit.
Lenders will typically auction the property if the timeshare was financed. Lenders will also attempt to collect the difference between the loan amount and the auction price. Defaulting on a timeshare loan will affect your credit and subject you to the typical practices of a collection agency.