Manually curating whitelists stops working once more than a couple of campaigns run in parallel. Building whitelist and blacklist workflows that actually scale.
Most teams start out curating whitelists by hand — check the dashboard, flag good sources, add them to the list — and that approach quickly stops working once more than a couple of campaigns run at the same time.
A minimum sample size before judging a source
A source that converted well on 15 clicks hasn't proven anything yet — set a minimum click or spend threshold per source before it becomes a whitelist or blacklist candidate, or you'll be chasing noise instead of signal.
Split lists by GEO and vertical
A source that performs well for nutra in one GEO won't necessarily deliver the same result for iGaming in another — a single universal whitelist across all campaign types usually loses to segmented lists, even accounting for the extra admin overhead.
Automate the blacklist more aggressively than the whitelist
Cutting an obviously underperforming source (high spend, zero conversions past the sample threshold) is a safe rule to automate; promoting a source to the whitelist is a call worth at least a quick human check, since a source can briefly look good on a small lucky sample.
Review lists on a schedule
Source quality shifts over time — a whitelist built three months ago can include sources that have since degraded. A monthly review catches that drift before it quietly erodes overall campaign results.
In short
- A source that converted well on 15 clicks hasn't proven anything — set a click or spend threshold before judging it.
- A single universal whitelist across all campaign types usually loses to lists segmented by GEO and vertical.
- Cutting an underperforming source can be fully automated; promoting one to the whitelist deserves at least a quick human check.
- A monthly list review catches source-quality drift before it erodes campaign results.
There's no universal recipe here, but the mistakes listed above cost the most and repeat the most often.