Give the test a limit
A spending limit creates a boundary for learning. Choose it in relation to the question, the outcome you care about and what you can afford to learn. Avoid treating a budget as a target that must be spent regardless of what happens.
Define the stop condition
Write down the circumstances that should trigger a review or pause. Include tracking failures and destination-page problems as well as weak results. A test that cannot measure its own outcome should not quietly continue consuming its full allowance.
Make approval rules explicit
Decide who can launch a test, increase its budget and change its scope. A proposal to spend more should show the evidence and the expected benefit. Clear responsibilities let the team move without repeatedly negotiating the same boundary.
Record changes in context
Keep a note of each significant change and why it happened. That context helps explain the results later and makes it easier to spot a pattern of exceptions. The objective is a useful history of decisions, not paperwork for its own sake.
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