Excellent and we'll put. Yes, indeed, she was overconfident and failed to account for all factors. That and her myopic view, and her fear of her boss all limited her view.Thanks for the clarification.
It has to be said though that Vadic is hardly the most stable individual and certainly makes choices based on the heart rather than the mind. She's obsessed and obsession can cause people to make mistakes.
Rather than being dumb, as has been pointed out, I think it's an instance of 'sheer fucking hubris'. She had control of the Titan's systems, having removed the ears, eyes and mobility of the crew. She thought she had it in the bag, but as any good Chess player knows, you have to focus on the whole board to avoid being blindsided. Data in this case was the element she failed to take into account.
I'd say her arrogance and overconfidence let her down, rather than stupidity.