Signal Decay Half-Life

Signal Decay Half-Life is the interval between a mention first appearing and the moment it stops being actionable, and it differs by channel and by client. A complaint on a review site can sit for a week and still be answered credibly; a misattributed claim inside a fast-moving short-form feed is effectively settled within hours. Agencies that price listening work by dashboard seats ignore this clock, then absorb the cost of after-hours escalation for free. The practical move is to assign each client a half-life per channel during scoping, then staff review cadence against the shortest one rather than the average. TikTok's maturation into a full marketing channel with its own KPIs makes this concrete: a platform now treated as a standalone strategy line also carries a standalone response window, and a retainer built on weekly reporting will miss it.