The values of the project should be kept in mind for all team members because th

The lack of explicit discussion about why and how the mission had to change created a wedge between participants. Reminding team members about the values underlying the project — promoting sustainability, urban livability, innovation — could have helped bring all of them back into the fold. Instead, the team found itself split between those enthusiastic about the new goal and those who clung to the old one.

People are predisposed to think that things are worse than they are, and they overestimate the likelihood of calamity. This is because they rely not on data, but on how easy it is to recall an example. And bad things are more memorable.