Small accounts often skip governance because the campaigns look manageable from memory.
That usually works until a page changes, an offer changes, or a test launches without a clean record of what was supposed to happen. Then the account becomes harder to review than it needs to be.
A workable governance layer can stay lightweight. It can be as simple as a naming convention, a short testing note, an expected review date, and a change log that explains what moved and why. The point is not bureaucracy. The point is to reduce ambiguity when traffic, offers, or landing pages change.
For publisher-style accounts, governance also protects page quality. It helps tie campaign activity back to the actual destination page, the disclosure state, and the intended audience. That makes paid traffic more accountable to the property it is promoting.