"If you work with the door closed, you won't be interrupted - you get your work done. You work with your door open, people come by and stop and chat and so on, so on but I've noticed very clearly at Bell Laboratories those who work with door shut may be working just as hard ten years later but they don't know what to work on. They are not connected with reality. Those who have the door open may very well know what's important. I cannot prove to you whether the open door causes the open mind or whether the open mind causes the open door. I can only establish the correlation and it was quite spectacular. Almost always the guys with the door closed were often very well able, very gifted but they seemed to work always on slightly the wrong problem."