If a Web page can be navigated sequentially and the navigation sequences affect meaning or operation, focusable components receive focus in an order that preserves meaning and operability.
Ensure the focus order is logical and intuitive.
Improves navigation for users relying on keyboard navigation.
Moving content around with CSS without considering its effect on the focus order.
Using a positive tabindex. If several elements have positive tabindexes, it becomes more and more likely that the focus order will not be correct.
Check cookie applications, they often have issues with this criterion.
There are tools, such as Taba11y that can help with testing.
The focus order may not be identical to the programmatically determined reading order (see Success Criterion 1.3.2) as long as the user can still understand and operate the Web page. Since there may be several possible logical reading orders for the content, the focus order may match any of them. However, when the order of a particular presentation differs from the programmatically determined reading order, users of one of these presentations may find it difficult to understand or operate the Web page. Authors should carefully consider all these users as they design their Web pages.