Two historical circumstances are mentioned as reasons why some retained an outward connection despite doubts: the effective implementation of Islamic law and the visible expansion of Muslim political power into surrounding regions. Such circumstances could make public adherence advantageous or withdrawal costly.
This illustrates that an outward affiliation may sometimes arise from calculations of security, law or social advantage, rather than from settled intellectual conviction. Yet identical conduct can have many motives, and it is invalid to infer a specific hidden belief merely from a person's continued affiliation or expressed disagreement.
The key distinction is between identifying plausible historical causes of a pattern and claiming certain knowledge of the inward motive of a particular individual.