Herd-like behavior describes some behaviors of groups comprised of many agents. Each agent to some degree mimics those around it, while also operating will a small degree of autonomy. It is an example of Emergent Behavior, where the herd operates like a single organism despite being the accumulation of many agents.
The term herd-like behavior typically describes activities that are not hierarchical, although the degree of autonomy typically varies between agents in the system.
A school of fish is an example of animal herd-like behavior. Each fish does not drift too far from the other fish, so that the fish stay together. However, the school will gradually drift around, as decided by the aggregate behavior of all the fish.
An example of human herd-like behavior is the bureaucracy of large companies. Large companies are stereotypically slower-moving and less inclined to rapid change than smaller organizations. One way of describing the problem is that a larger objects require more inertia to change their velocity than smaller objects. Another way of describing the problem is that an organization with more agents will require more time for information and intentions to propagate mimetically through the organization.
Due to the gradualism described above, large organizations are "hill-climbers" on the evolutionary landscape. This stifles innovation when compared to nimble competitors which can rapidly improve and plan from first principles. However, these organizations are highly responsive to outside feedback.
Large organizations can behavior less herd-like with strong leadership that forces a plan to be carried out. However, rigid leadership can stifle innovation, because it reduces the ability of each agent in the herd to experiment semi-independently. The mix of some experimentation within the scope of a shared purpose is a strength of larger organizations.