Creating a user interface that is consistent across pages adheres to which WCAG principle?

This maps to Understandable because consistency across pages makes navigation and interaction more predictable. In HubSpot CMS work, repeating shared interface patterns helps visitors recognize where key elements appear and how they behave from one page to the next. That predictability reduces confusion and supports a clearer user experience, which is the core purpose of the Understandable principle. HubSpot also supports this through global content , which keeps repeated elements like headers and footers consistent across templates. A consistent interface is not mainly about visibility, input method, or technical compatibility; it is about making page behavior easier to follow.