I agree, you never want to say a weakness like being late. It should be something that you have identified about yourself, and are now trying to work on. For example; a weakness might be not being confident about speaking in large groups, but however when I was at school I joined the debate team to try and get practice doing this. It doesn't have to be this but you get the idea.
Always identify how you're already trying to improve.
Also for questions to ask them, NEVER talk about money or job benefits, ask something about the company that shows you've done your research, like the success of a product they recently launched or something similar.
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Velcro - what a rip off.