Activation & operations
In-flight optimisation
In-flight optimisation is the ongoing adjustment of live campaigns - budgets, bids, audiences, creative, placements - based on delivery and outcome data during the flight. Good optimisation follows diagnosis; change for its own sake resets learning and destroys readability.
In practice
The discipline is separating signal from noise: enough data to judge, a hypothesis for the change, one variable at a time where possible, and a record of what was done and why.
Reallocation between lines, guided by marginal efficiency, is usually the highest-value optimisation available - and the one spreadsheet-based operations perform least often.