Why do browser agents fail at checkout?
Checkout is where agent failures cost the most and happen most often. It is also the part of the site with the most defences, the most third-party components and the least tolerance for a wrong click.
The usual failure points
- Address autocomplete that overrides typed input, leaving a half-filled or wrong address.
- Card fields inside a payment iframe the agent cannot see into.
- 3-D Secure or one-time codes that require a phone the agent does not hold.
- Delivery or shipping options rendered as unlabelled tiles or images.
- Discount and upsell interstitials inserted between steps.
- A "Place order" button that stays enabled while the request is in flight, inviting a double submit.
Silent failure is the dangerous one
Worse than an agent that gives up is an agent that reports success on a page that never confirmed anything. The customer believes the order exists. Support finds out later.
What actually helps
Give each checkout step its own URL. Label every option in text. Disable the submit control while processing. Show a confirmation with a stable, findable order reference. And decide deliberately which verification steps you require — some of them are the point, and should stay.
Know your number
The only question worth answering: out of ten agent attempts, how many end in a real order? PlateTale measures that and shows you the step where the other ones died.
PlateTale