Some candidates approach preparation for questions in the viva like it’s a great big quiz.
If they try to think of every question that examiners could ask and make notes, they’ll have all the answers. But whenever they have another thought, or get another question from a colleague or supervisor, that’s something else to take account of. Another question and response to add to memory. At some point the weight of all that could crush a person.
A better process for question prep: find, make and use opportunities to get practise answering questions.
A process for the viva: pause when you get a question, think it through for a moment, then answer.
You can’t anticipate every question but you can be ready to answer any question.