Here's two quotes reflecting this:
John Malone: Most of the money I've made in my life has been when other people don't like what's going on. When things are cheap, that's opportunity.
Jack Ma said something to the same extent. If 10 out of 10 people agrees with you, then nothing needs to be done. If there is just one or two smart, close friends who criticize your idea but think there might be something worth pursuing that is interesting.
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