Change management, applied to marketing, refers to the structured process of reviewing, approving, and tracking changes to live campaigns and assets — as opposed to an ad hoc process where anyone with access can edit a live page or adjust a live ad without review.
Structured change management doesn’t need to slow a team down; its purpose is to make sure a change that touches multiple systems gets checked and approved consistently, rather than depending on whoever happens to be making the edit to remember every downstream implication.