Narratively this makes sense - Daedra-worship was always part of the Dunmer culture and was thus comparatively common in Morrowind, even during the reign of the Tribunal, and there were still many Daedric ruins there where unbound Daedra of all levels from Scamp to Golden Saint could be found: but there are no such ruins and no such cults in Skyrim at all. There are far fewer unbound 'wild' Daedra in Skyrim than there were in the previous two Elder Scrolls games, Morrowind and Oblivion.
Many of these summonings are successful and those Daedra serve their masters without fail, but even more summonings go wrong and result in unbound beings turning on their masters. Despite the lasting ramifications of the Oblivion Crisis, conjurers across Tamriel could not resist the allure and power associated with summoning Daedra and attempting to command them. Only two of these types of Daedra appear in Skyrim, however: the atronachs and Dremora.
An atronach under the command of a conjurerĭaedra are creatures and sentient beings that can be found across the vast expanses of Oblivion.