To tell the job interviewer about weaknesses, be honest but don’t mention being deficient at something that is a main part of the job. It is okay to talk about needing improvement in typing skills when applying for a non-administrative role, but not for a job as an office manager or data entry clerk.
Any time a weakness is mentioned during the interview, follow it up with information about how it is being improved. If your weakness is not being organized enough in the office, explain how you're learning to pay more attention to proper organization to create an effective office environment. This allows the interviewer to see that you understand your weaknesses and are striking to improve them.
When discussing weaknesses, keep the focus on business. Do not talk about personal weaknesses unless they relate to work in some capacity. Talking about how being on time is something you're working on is fine since it is personal, but still has to do with getting to work on time.
Don’t be afraid to mention weaknesses that some supervisors might see as a good trait, but avoid mentioning things that are obviously not a weakness. Saying working too hard and long hours is just another way of complimenting yourself. However, a good weakness to mention is that working too hard on one task is something that needs to be overcome in order to balance the work throughout the day better.