The myriads of minds that were uploaded into the Jovian Collectives lack individual thought and experience. As a whole, the collectives do not perceive time and space in the same manner as normal humans do. In some way, all Collectives constantly experience a very complex array of overlaid dreams and simulations.
The collectives found found that without fresh experiences not borne out of a simulated virtual environment, their artificial minds began to deteriorate. This initially set in after about a century of the establishment of the first collective. In searching for a cause of this decay, the collectives found that the compound, digitalized consciousnesses constantly required new, authentic inputs. The steady stream of new converted humans who joined the Great Houses turned out to be too unpredictable to guarantee the long-time survival of most collectives.
What contributed to this effect was that as the Great Houses grew in size, their perception of time became so distorted that that they increasingly had difficulties interacting with the outside world. To amend this, Collectives created artificial beings capable of individual thought and experience that were meant to mingle with biological humans. They would be able to have individual experiences outside of the collectives, that could then feed fresh impressions and prevent deterioration. They could also serve as interlocutors and ambassadors between the Collectives and the Inner System.
Avatars or "Evers" are artificial cyborg bodies housing a unique consciousness that has been woven together from bits and pieces of disparate personalities of a single Great House. Each Great House has produced several thousand of these beings. Today Evers are quite numerous in the Inner System. Most will identify themselves as such towards baseline humans. However there have been many cases of avatars that did not, who instead kept their true nature secret. This has resulted in many vicious conspiracy theories. Also, rumor has it that Evers exist among humanity that themselves do not know what they are.
Most biological humans regard known Evers with at least some suspicion. A small number of the artificial persons have achieved high levels of individual success within human society none the less. Most Avatars are visually indistinguishable from biological humans or anthroform shells. After an indeterminate period of time, an Ever will return to the Jovian Moons to re-enter its collective and donate its life experience and its entire consciousness back to the Great House that once birthed it. The individual Avatar ceases to exist as such at this point.