Familiarity normally prevents trust from becoming consciously examined. [causal]
For the most part, closer familiarity keeps the problem of trust from even becoming a matter for reflection. And when reflection does occur in such circumstances, the taken-for-granted nature of familiarity will be lifted. A gulf of obscurity opens up even with respect to things and people nearest to one, which doubt removes into a surprising impression of foreignness.
Niklas Luhmann, Trust and Power, loc. 172