Compare two attempts fairly

Hold the question steady

Use the same task, input and definition of success for both attempts. If the question changes halfway through, treat the later attempt as a different investigation. A familiar label does not guarantee that two readings describe the same piece of work.

Write down the one condition being varied. This creates a small anchor for the comparison and makes accidental changes easier to spot.

Keep ordinary variation visible

A repeated task rarely gives exactly the same result every time. Several modest attempts can show whether a difference is consistent or just part of normal variation. Keep unsuccessful attempts visible too; quietly excluding them can make a fragile method appear reliable.

A middle value and a description of the range are often more informative than the single best result. The right summary depends on the question, but it should not conceal a pattern that would change the decision.

Allow an uncertain result

Sometimes conditions cannot be held steady enough to separate an improvement from background variation. Record that limit. An inconclusive comparison is still useful if it prevents a premature decision and identifies the condition that needs better control next time.