Count finished work. Time the current process and the AI-assisted process through the same approved result. Include checking and fixes. If the new process takes longer, those extra hours enter the cost.
Keep time separate from money. Hours freed can help a team take on more work. They become cash savings only when a planned expense is avoided or reduced. Count extra profit or avoided losses separately and only with evidence.
Use break-even as a test. The minimum use rate is how much suitable work must use AI to cover first-year fixed costs. Compare it with observed use during a trial; it is not a prediction.
Decide with evidence. The less- and more-use views show how the answer can change. Before expanding, compare a limited trial with the old process, name an owner, and write down what would make you pause it.