The upgrade window opens in service. Most stores never see it
A customer brings in a three-year-old SUV for its 30k service. She has positive equity, an 800 score, and a payment she'd happily keep flat to drive something newer. Your advisor writes the RO and hands the keys back. Nobody told sales she was even in the building.
Missed signals
Advisors aren't salespeople, and the desk can't stand in the service lane all day. The signal that would have flagged her as a trade sits in three different systems, and nobody is cross-referencing them while she waits on an oil change. So she leaves.
Do that seven hundred times a month and your best sales opportunities are walking out the service exit.