Of course there are downsides to such prizes. When money is given after the fact, only individuals and organizations that can self-fund can participate, often elbowing out the little guy. Innovation prizes work better in inducing scientific breakthroughs than in causing social change. And it's not an easy task to pick an innovation that is ambitious yet achievable. But even if innovation prizes aren't as much of a panacea as some would have you believe, I think they can play an important role in driving neglected research forward.
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