Why were early electronic pill boxes unsuitable for complex, multidrug regimens?

They were limited to a single medication type.

While electronic pill boxes represented an improvement over simple pill bottles for monitoring, they had a significant structural limitation when applied to the care of chronically ill patients. These early devices were typically designed with compartments intended to manage only one type of medication at a time. In contrast, many patients managing chronic conditions require complex, multidrug regimens (polypharmacy), necessitating multiple pills taken at various times throughout the day. Because the standard electronic pill box could not adequately store and track multiple distinct medications simultaneously, its utility in real-world chronic care settings, especially in research settings where complex regimens are common, was severely restricted, forcing researchers to seek alternatives like EMMS.