From a complexity perspective, there is a good reason why teams in an organization must be able to make decisions together. This follows logically from the Darkness Principle:

Each element in the system is ignorant of the behavior of the system as a whole [...] If each element ‘knew’ what was happening to the system as a whole, all of the complexity would have to be present in that element. – K.A. Richardson

What we learn from the Darkness Principle is that each team member can only have an incomplete mental model of the whole project. That is why they have to plan and decide together. It is why Scrum and Extreme Programming require the whole team to be present during planning meetings and daily stand-ups. The team members must aggregate their limited mental models and agree on a joint approach.

Some managers are not comfortable with the idea of allowing a team to make decisions together. They feel they lose control over what's happening when teams make decisions without them. Managers assume that decisions must be enforced, or otherwise anarchy unfolds. B