Do you lead from the front? Or the middle?

Why do managers erect barriers and distance themselves from the people they lead?  

Decisions made by a group, on average, are better than decisions made by individuals, according to a study conducted by Gayle W. Hill at Michigan State University.  The study found that by pooling and aggregating disparate pieces of information, groups form better decisions. 

Most managers feel pressured to make good decisions, yet many are reluctant to seek advice from the people they lead.  On a consulting job, I had a new manager tell me NOT to ask the opinions of her team.  Everyone else on the team had worked there for years.  She was brand new, but she didn’t want to know their thoughts. 

What on earth was she thinking?