Most media agencies are paid a percentage of what their clients spend.
The arrangement is so common that it rarely gets examined. It is easy to administer, it scales with the account, and it sounds fair: the agency does more work when the budget is larger, so it earns more.
Look at it for one minute from the client's side and the problem is obvious. The agency's revenue goes up when the client's spending goes up. It does not go up when the spending works. Every recommendation the agency makes about budget, channel, or pace is made by a party that is paid more if the answer is "more."
That is not an accusation of bad faith. Most people in the industry are trying to do good work inside a structure that rewards something else. It is simply a conflict of interest, and it has a logo on it.
What the incentive produces
Percentage fees shape behavior in ways that are easy to see once named.
Budgets rarely come down. When a channel is underperforming, the recommendation is to test more creative, not to pause. Cheap inventory is attractive because it inflates volume at the same fee rate. "Always-on" spending is defended on principle. Reports emphasize scale over outcomes. And the agency has little reason to tell a client that a channel is closed to their category, because a closed channel is budget that cannot be placed.
None of that requires anyone to be dishonest. It only requires people to respond to how they are paid.
Three rules that remove the conflict
We run media on three rules, and we publish them because they are the answer to the question every media buyer should be asking.
A flat fee per account, never a percentage of spend. The fee is for the work of running the account: setup, inventory standards, verification, optimization, reporting. It is the same whether the client spends thirty thousand or three hundred thousand. The only way to earn more is to earn the next account, which happens when this one works.
We never front media spend. The client pays the platforms and partners directly, or funds a media account in their own name. The moment an agency lends money to buy media, it becomes a creditor with an interest in volume, and it gains control of the account history, pixel data, and platform relationships that should belong to the client.
Fixed fee against written scope, never hourly. The scope says what will be done, what will be delivered, how long it takes, and what it does not include. Hourly billing rewards slowness. A percentage rewards volume. A fixed fee against a written scope rewards finishing.
How to ask for it
A client does not have to hire us to use this. Ask any media partner three questions.
If I halve my budget next month, what happens to your fee?
Whose name is on the ad accounts, and who holds the pixel and conversion history if we part ways?
What is in scope, in writing, and what is excluded?
The answers tell you what the partner is actually selling. A partner paid a percentage is selling placement. A partner who fronts spend is selling credit. A partner paid hourly is selling time. A partner on a flat fee against written scope is selling the outcome of a defined piece of work, and can be judged on it.
The honest limit
Flat fees have a floor. Below a certain account size the work does not cover the fee, and a good partner will say so rather than take the account and under-serve it. That is why we publish a minimum and the next step in the same proposal: the client should always know what the engagement costs, what it includes, and what it would cost to go further, before anyone starts.
A fee structure is not a detail of the contract. It is the strongest predictor of the advice you will receive.
lowob takeaway: Percentage-of-spend fees pay the agency for volume. Flat fees per account, no fronted spend, and written scope pay for the work, and leave the client holding their own accounts and data.