How does automatically checking answers make 'accessibility suffer'?

I would like to set quizzes to 'Automatically Check Answers' so that the user doesn't need to hit Check every time. Under the Automatic checking option in the back end it says, "Enabling this option will make accessibility suffer, make sure you know what you're doing.".....what does this mean? How will it suffer?

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icc's picture

Automatically "submitting" the answer to get a grading without the user making an active choice e.g. through clicking a button is not considered good practice according to the WCAG guidelines. I do not recall the exact succession criteria for this.