Choose a weakness that will not prevent you from succeeding at the job you are interviewing for. Be honest and positive in your answer. Mention any positive aspects of the weakness you name (very few weaknesses are completely negative), and focus on what you are doing to change or improve the issue.

"One of my weaknesses is my efficiency and desire to complete a task as quickly as possible. This can be helpful in certain situations when speed is a necessity. There are also times it causes me to miss opportunities, though. In the past, if an email came into my inbox with a simple question, I would quickly look them up in the system and reply with the answer. In doing that, I have succeeded in providing the employee with a fast answer to their question, which on the surface seems like excellent customer service. I've realized that by taking a little bit of extra time to think through why they are asking, I might be able to provide extra information that could help. I've been working on this by pausing before hitting send on any email and asking myself what else the person might want to know or why they are asking the question."