After you pay off your phone if there's an issue with your phone they can't make money on that they're obligated to fix their strategy is to transfer you to 7 different people (not an exaggeration), waste 4 hours of your time on the phone and/or going to different stores (also not an exaggeration) until you give up and upgrade. They should just say they won't help you with your phone after it's paid off so you know you need to upgrade without wasting your time.
Recommendation: Assume Verizon won't help with your phone after it's paid off and you'll need to upgrade.