A team must choose between three designs with different strengths. What analysis method produces a decision rather than a discussion?

The method

Evaluate the options against concrete scenarios rather than against abstract qualities.

Comparing designs on "scalability", "maintainability" and "flexibility" produces a discussion, because each person means something different by each word and every design scores well on the ones its advocate values.

Comparing them against specific scenarios produces a decision:

• "The corpus reaches ten million documents and query volume triples."
• "A team member who did not build this has to debug a latency problem at 3am."
• "We need to change the ranking logic after a customer complaint."
• "The primary node fails during peak."

For each scenario, each design produces a describable outcome, and the outcomes are comparable.

Why this works

It forces the abstract qualities to be cashed out. "More scalable" becomes "handles ten million documents without re-architecting", which is either true or false rather than a matter of emphasis.

It also surfaces the scenarios nobody had considered, which is frequently more valuable than the comparison itself.

What to include in the scenario set

• The growth scenario, at a specific size derived from the business plan rather than from imagination.
• The failure scenario, since designs differ most in how they fail.
• The change scenario, because most of a system's cost is in changing it.
• The operations scenario, which is systematically omitted and is where the difference between a design that is elegant to build and miserable to run becomes visible.
• The exit scenario: what it costs to move away from this choice.

The output

A written record with the scenarios, the outcomes, the decision and the conditions that would change it. The conditions matter most: "we would revisit if the corpus exceeds X or if we need per-tenant ranking" is a monitoring instruction disguised as a decision record.

The discipline that prevents the common failure

Weight the scenarios by likelihood before evaluating, or the exercise becomes a search for a scenario favouring the preferred option. Agreeing the scenario set — and its weights — before comparing is what makes the method a decision procedure rather than a justification exercise.