Forming entities on a 3rd Density world incarnate almost continuously early in their 3rd Density existence, unless there is a lack of opportunity. Just after an intelligent species has been genetically engineered, however, forming entities usually find the opposite situation - more than enough bodies awaiting an incarnation, a choice. This is due to many forming entities aborting upon death, so that a stable or growing population has an increasing number of bodies but few reincarnating entities. During these early years the majority of intelligent, conscious, creatures are in fact virgin territory for a new forming entity, with the minority being occupied by a reincarnating spirit. The birthing envoys, at this stage, allow the process to occur automatically. In due time they step in to start guiding incarnations, but do this without having to resort to the imposition of any physical restraints.
We have mentioned that spirit guides force an Out-Of-Body entity back into its body, and that birthing envoys gather up entities leaving a dead or dying body. How is this done without physical restraints? If spirits can pass through walls and travel freely, would they not simply flit away from the entities watching over them? Order is maintained in these situations by what we would best describe as a force of will. Entities acting as school yard monitors on a 3rd Density world are operating in 4th Density, and many have arrived from even higher densities to do service. Spiritually, they have more bulk, more mass, and certainly have more wisdom and skill to coax and manipulate lesser entities.
An immature entity leaning toward Service-to-Self is led to an environment, among more mature entities, where it can be the center of attention, and thus it has no urge to wander. Immature entities leaning toward Service-to-Other are placed together with a peer that needs healing, and participate with higher density entities in this process. They likewise, given their sense of purpose, have no immediate urge to wander. Where recently incarnated entities have unsettled business and wish to visit the living or to visit certain settings, a field trip is essentially arranged. Some of these field trips go on for years and even hundreds of years, producing what you term hauntings. During this time the distraught entity is in the company of its guides, who normally keep watch over a number of other immature entities at the same time. Nevertheless, the guides can be called upon to attend to the haunting entity, when need be.
Over time a 3rd Density world evolves to the point where most of its intelligent creatures are occupied by reincarnating entities, and unless there is a drastic reduction in the population, waiting periods only occur when the birthing envoys determine that the next incarnation requires special circumstances. During times of a rapid increase in population, such as the Earth has experienced during the past half century, no reincarnation occurs in many intelligent creatures, but a forming entity may begin. As is usual in these circumstances, most will abort. Thus, when the harvest time comes, during the pending pole shift, there will not be close to five billion souls to be escorted to new homes, but only a little more than a billion. Where a life is lived passively, with little challenge and exhibiting no initiative, a forming entity is unlikely to do anything but dissipate upon death. There is nothing for the birthing envoys to gather.