What are some mistakes you’ve made in previous jobs?

You are being invited to tell tales against yourself. Whatever you admit to, make sure it’s fairly innocuous and did not involve losing money or time for your company.  Be quick to explain what you learned from a past mistake and how you rectified things.E.g, perhaps you didn’t document your activities or keep your boss up to date as much as you should have, making it difficult for others to fill in when you were out sick or on vacation.  But once you were admonished as to how this inconveniences your co-workers, you now keep one of the most thorough paper trails in your firm.