There’s a “wisdom of crowds” effect related to influence.
One person can develop a strong opinion, and it can be near impossible to change their mind. But crowds are different. There will be enough individuals in a crowd of people whose minds aren’t yet made up, that can be directly influenced in your direction. Enough of those folks together can then directly influence others in the crowd as well.
Seth Godin put the distinction between individuals and markets into perspective in his book The Dip:
Influencing one person is like scaling a wall. It you get over the wall the first few tries, you’re in. If you don’t, often you’ll find that the wall gets higher with every attempt.
Influencing a market, on the other hand, is more of a hill than a wall. You can make progress, one step at a time, and as you get higher, it actually gets easier. People in the market talk to each other. They are influenced by each other. So every step of progress you make actually gets amplified.