State how long requests can be canceled
An order is usually a commitment. G164 is about the sites that choose to leave a window open anyway. After the form is submitted, say how long they have to amend or cancel. Say exactly how to do it. W3C accepts that the procedure may not be online at all, and might mean written notice to an address, as long as the page says so. This is a sufficient technique for 3.3.4 Error Prevention at Level AA, for transactions that create a legal commitment, move money, or delete data. The part that decides whether it works is ours rather than W3C's. The window has to be stated where the user acts and where they will look afterwards, not in a policy page nobody reads, because a right nobody knows about is a right nobody uses.
How we find it in an audit
Our reviewers place a real transaction and read what comes back. Does the confirmation state the window in plain words? Does it say what to do, and does the route it names actually work? We follow the cancellation path all the way. A stated window that ends in a phone number nobody answers is a promise rather than a mechanism.
How affected users experience it
Everybody makes ordering mistakes and some people make more of them, because navigating by keyboard or by speech means more steps between choosing and confirming. Someone with a cognitive disability may realize an hour later that they picked the wrong item. A clearly stated cancellation window turns that from a loss into an errand, and it is the cheapest error prevention on this list to implement.
Passes vs. fails
Passes
The confirmation states 'You can amend or cancel this order within 24 hours from your account page', and the account page can genuinely do it.
Fails
An order confirmation says nothing about whether the order can be changed, and support later explains it could have been, within a day.
Other ways to satisfy this rule
7 guides on this site are filed under 3.3.4 Error Prevention (Legal, Financial, Data). W3C lists this one as sufficient for that rule on its own. Implement it correctly, in a way your readers' software actually supports, and the rule is met.
- G98sufficientLet users review answers before final submission
- G99sufficientMake deleted data recoverable
- G155sufficientAdd a confirmation checkbox before final submission
- G168sufficientAsk for confirmation before completing risky actions
- G199advisoryConfirm success when a submission works
- SCR18advisoryValidate in the browser and describe the error
This guide is our interpretation of W3C technique G164: Providing a stated time within which an online request (or transaction) may be amended or canceled by the user after making the request. W3C publishes its techniques as guidance rather than as the standard, and says so on every one of them. The success criterion is what conformance is measured against, and a technique is one documented way to meet it.