What should an engineering decision log capture to inform future work?

• A. Rationale behind decisions.
• B. Alternatives considered.
• C. Rationale, alternatives considered, and test outcomes.
• D. Test outcomes only.

Answer: (C)

A good engineering decision log records the reasoning behind choices, the alternatives that were considered, and the results of testing. This combination provides a complete trail that future teams can follow. The rationale explains why a particular path was chosen in light of requirements, constraints, and risks. The alternatives show what other options were weighed and why they were not pursued. The test outcomes supply objective evidence about how the design performed, where it met expectations, and where issues arose. Together, they let future work reproduce decisions, revisit tradeoffs, and build on what was learned rather than redoing the same analysis from scratch. If you only note why something was chosen, you miss the evidence that supported it; if you only record test results, you lack the context for why those results mattered; if you only list alternatives, there’s no justification for the final path. Recording all three ensures the team can make informed, efficient progress next time.