If your car were a total loss, this "gap" could translate into thousands of dollars that you would still owe after your insurance paid you the actual cash value of your vehicle

In the event of a total loss, any remaining balance due on your loan or lease after the payment from your insurance company is waived by the dealer/lender.** In other words, should a balance be left over after your insurance pays the market or cash value, all you will have to pay is your insurance deductible.
** Does not include any late fees or past due amounts.
GAP Plus (GPP) waives the same out-of-pocket expenses as GAP, and also includes your insurance deductible up to a maximum of $1,000.