Contrary to popular belief, you do want to give a real weakness instead of a “fake” weakness. However, you must frame it in a way that shows you have a strong awareness about this weakness, and have made significant steps to improve.
Try to avoid cheesy weaknesses like “work too hard.” Weaknesses like “focus too much on the details, lose sight of the bigger picture”, “need to be more thoughtful about when to speak up and when not to”, “learning how to prioritize the right kind of work” etc. are some examples of real weaknesses that also aren’t a deal breaker since they’re easily fixable.
Avoid red flag weaknesses like “lose motivation sometimes”, “lack attention to detail”, etc. since motivation and attention to detail are core elements of the job.
After explaining your weakness, make sure to tell a story about how you improved it. Ideally, this would be related to work, school, or an extracurricular experience. Explain the context of the situation, how you identified the weakness, the steps you took to improve it, and the final result of your improvement.
This will demonstrate that you have the ability to take feedback, recognize your weaknesses, and improve upon them – a critical skill in any job.