Hieroglyphs were always closely related to the traditional Egyptian religion, and indeed, it was always only a small percentage of the population that could ever transcribe them, centered around the religious caste. Their use was primarily on monumental works, and the writing system itself evolved over time. When Egypt fell, first to the Persians, and then to the Greeks, and finally the Romans, the domestic ruling and religious castes were progressively weakened. Once Christianity took hold, it was the death knell.

In general though, the transition away from hieroglyphs was similar to the transition seen elsewhere from logographic/pictographic scripts to phonetic scripts for the same reasons it occurred elsewhere.