68% of users abandoned checkout at the address step. There was no error message when an address fell outside the delivery zone — the screen just quietly refused to advance.
Rebuilt the address flow around a live delivery-zone map, added instant zone feedback, and cut the form from nine fields down to four. Out-of-zone users get a waitlist capture instead of a dead end.
Checkout completion up 41%. Revenue per session up 27%. Support tickets about "checkout not working" dropped to near zero.