Frequency capping limits how often a given viewer is shown the same ad or campaign over a period. Without it, viewers get the same spot repeatedly in one session - a notorious streaming annoyance that drives irritation and erodes both ad effectiveness and content enjoyment.
Implementing it well requires identity and state across the session and across devices, which is harder in server-side insertion and in the cookieless, multi-device OTT world than on the old web. Good frequency management improves viewer experience and advertiser value at once, but it constrains fill, so it is another balance the ad stack must strike.
