Seven edge cases that quietly break checkout
Checkout works on the happy path. These seven situations are where real customers run into trouble.
Almost every checkout passes the happy-path test: add an item, pay, see the confirmation. Real customers are less predictable. These are the situations we check first.
- Pressing Pay twice, or tapping it again because nothing seemed to happen.
- Using the Back button after applying a discount code.
- Names with apostrophes, accents or emoji in the address and card fields.
- Totals in other currencies and number formats, such as 1.000,50 and 1,000.50.
- A slow or dropped connection in the middle of payment.
- Two browser tabs open on the same cart.
- Coming back to an abandoned cart days later, after prices changed.
How to check your own
Pick one flow and spend twenty minutes trying to break it like a real, slightly impatient customer. You will usually find something worth fixing.