I had an interesting experience recently. I was working with a team as they went thru their sprint planning. They had figured out their capacity based on yesterday's weather and their average amount of interrupt. The product owner suggested the sprint goal and they started picking stories based on the goal. They reached the point where one more story met the sprint goal, but put them over their estimated capacity. The scrum master pulled it into the sprint and said he thought they could get the story done.
At this point I stepped in and commented that it was up to the developers to decide if they wanted to commit to the work. The developers remained silent. I made a comment about not over-committing and finally some comments were made by the team to keep the story out and pull it in if they get everything else done.
So what happened here? Why didn't any of the developers speak up when the extra story was first pushed on them? Based on this and other observations in the organization, I attribute it to a lack of psychological safety. The developers didn't feel safe to say "No, that's more than we can get done."
I wrote another article recently talked about group think. The two ideas are related. Group think exists in situations where people don't feel safe stating an opposing view. But psychological safety goes much further than that. A team without psychological safety will be reluctant to take chances, it impacts their ability to learn, they will be afraid to admit mistakes. In general, it keeps them from becoming a high-performing team.
So how does a team fix this? The reality is they can't. It's not the team but the organization around the team that will or won't create a space of psychological safety for the team to exist in. Product owners and chief product owners need to be coached to understand how their actions impact the environment. It's starts with them showing they are vulnerable, by admitting their mistakes. They need to encourage teams to take risks and not punish failure but show how it can be used as a learning event. It's only when teams see these kinds of behaviors that they will start feeling safer, and next time a developer will speak up and say "No, that's more than we can get done."