What is software testing? — quiz

A team finds an ambiguity in a user story during refinement and clarifies it before any code is written. The fix takes 15 minutes. The same defect, caught in production, would have cost an estimated $10,000 to handle. This illustrates which principle?

• Testing should always be deferred to QA at the end
• Bugs caught earlier are dramatically cheaper to fix
• All defects cost roughly the same regardless of timing
• Documentation prevents all production bugs