Continue reading the book "The Art of Thinking Clearly", by Rolf Dobelli, on social proof.
Social proof is a phenomenon that people copy others' behaviors. When things happen, lots of people naturally look at what others do, then take actions.
I agree with Rolf, that "social proof is the evil behind bubbles. The more people do the same, the better it will be justified. If fifty thousand people say something foolish, it's still foolish."
How to break it?
When facing a situation, make your own decision first. If you may need to adjust later, that's ok, but do start with thinking what's the best next step for YOU, first. Think if there's any reason that people are going one direction together, think if it makes sense, and if not, don't be afraid to go your own way.