Ad-tech
Daily cap
Per-affiliate or per-source daily conversion limit set by the advertiser.
A 'cap' is the maximum number of conversions per affiliate per day that the advertiser will pay out on. Caps protect the advertiser from over-spending on bad-quality leads and let the advertiser-side call center pace its capacity. Once the cap is hit, traffic gets either paused (best case) or routed to a fallback offer at lower payout (worst case, common). Smart operators bake the cap into their bid model and pause once the cap is hit.
Example
Insurance lead-gen offer caps at 50 leads/day per affiliate — operator hits the cap by 1pm and either pauses traffic or shifts to a backup auto-insurance buyer at $14 CPL vs the primary's $32.