^ maybe saying that you're a perfectionist or a workaholic?
What coblin said. It's probably what *everyone* says and it gets old really, really fast.
The best responses are framed around actual weaknesses or flaws that you had. You state what you're weakness really is - but also how you are mitigating it (think about framing your response to the S.T.A.R technique - Situation/Task, Action, Result).
I think I used a flaw of mine that I do not enjoy doing long, repetitive tasks but then also mentioned that a strategy that I was using to mitigate this issue was to break the task down into sizable chunks and 'splitting' up my day to reduce the risk of being bored of the work.
Of course the responses will vary from person to person - and that will make you more unique in the eyes of the recruiters...as opposed to 'I'm a perfectionist'.