“He used a technique I later came to call the virus of doubt. It’s a way to get into people’s heads, remind them about a daily frustration, get them annoyed about it all over again. If you can infect them with the virus of doubt—“Maybe my experience isn’t as good as I thought, maybe it could be better”—then you prime them for your solution. You get them angry about how it works now so they can get excited about a new way of doing things.”