In a peer-group, a dangerous syndrome can occur: peer-group syndrome. Have you ever found yourself in a situation where you've suppressed your opinion, to let others express their, to make sure you're not off base? Afraid your thoughts are so too far away from the rest of the team? Have you noticed anyone else doing?
This is an important condition to pay attention to, in yourself and your team. It can seem innocent. In a Slack room, you see your boss typing an answer to a question. In response, you stop typing your opinion, waiting to see your boss'. In a meeting situation, you let the senior developer speak before you do. When the group or Slack room comes around to the opinion expressed by the senior member, your move on—never expressing your initial opinion, content with what came out. Your idea may not have been as refined, however, often it can strike a valuable chord in someone else. Plenty of times I've seen junior members bringing a crazy new angle to a problem, where a senior ran with the idea along with the junior—spurring some incredible ideas. It's paramount to create an environment where this can happen.
This syndrome rapidly evolves into contributing to groupthink. Your team gets so used to the behaviour, that they start confusing consensus for the best possible solution. This is rarely true. Some people need to be pushed for their opinion, as they default to silence. Others don't voice it because of peer-group syndrome: letting an opinion form from the group. The senior members may not consider additional solutions because a "decent" solution has unfolded.