Some effects grow slowly enough that the original cause escapes suspicion.

Slow growth is excellent camouflage. When the effect builds by small increments, each day looks like the one before, so no single moment triggers suspicion, and by the time the size is undeniable the cause is far behind you and hard to connect. Gradual is how most serious things arrive.

Measure a few things you would otherwise judge by feel. Weight, spending, hours, how often you see your closest people. Numbers taken over months notice drift that daily impressions are built to miss.