This misunderstood relationship gets often mixed up with the dominance relationship. The social cohesion gets claimed when a coordinated direction or activity change shall proceed. Somebody has to decide when, where and at what pace to go. The lead in this case is independent of the rank in the pack.
Leaders are such, that are, due to their knowledge and experience or their exceptional calmness and decision-making, capable of leading a group in a coordinated manner to reach a common advantage.
“You must be the pack leader, you have to walk first through the door, the dog has to follow you.” Is the advice of people that obviously never studied a wolf pack.
When wolves are wandering, almost never the alphas are up front. At least as long as they are in a known area, there are always some lower ranking young wolves ahead, while the highest-ranking wolves stay in the centre together with their “royal household”. Only in unknown area it occurs that the highest-ranking wolves take over the leadership. When they go for hunting, there are the tracking specialists up front, anyway.
So when one believes in walking through the door first, but does not know what to do while walking the dog, or even worse, always walks the same, boring way without offering interesting variety, this person is not a leader.
The leader does not care if everybody is following, but the group cares if the leader departs. So when you open the door and your dog walks out, does he run away or does he stop, look for you, even perhaps come back inside?
If you and your dog have a healthy relationship and a good bonding, you can – wherever – change directions without informing him or hide, he will always follow and search for you.