They call it gap insurance. It’a normally less than 1000 bucks for the life of the loan. Someone totals your van and the pay out is not enough gap will cover it. It cover the “gap” between actual cash value (what you get paid by the other parties insurance) and what you owe on the note.
Everything looses it’s value over the course of it’s life. Even your home if it’s in the wrong area or poorly maintained.
My house doubled in value so that’s a bad example. My 2003 Cavalier has kept its value over the last year. I can sell it for what I paid for it.