CMP.8:8 - Common Anti-Patterns and How to Avoid Them

Tempting move	Failure	Useful repair
Treat a good objective value as an admissible answer	Rounded constraints can admit an invalid object.	Preserve constraints or construct and justify recovery.
Stop because adjacent refinements agree	Both can omit the same contribution.	Bound the unresolved tail or use a justified enclosure.
Increase precision for every failure	Input uncertainty or subject-model error can dominate.	Identify the limiting contribution first.
Use a relative error at a zero target	The ratio is undefined or unstable.	Select an absolute or otherwise meaningful comparison.
Transfer an approximation guarantee to a changed output	Near-optimal value need not identify all optima or preserve derivatives.	Reconstruct the comparison for the new requested result.