The original title is "Your Test Suite Isn't Slow. It's Accumulating Decisions"

Short summary

Browser test suite degradation is usually accumulated reliability debt from small technical decisions, not inherent flakiness. Environment differences like CSS motion preferences, feature flag states, and optimistic UI transitions cause failures that look random but are actually consistent responses to different inputs. Teams should make environment settings explicit in test config and capture full context on failure.

• •Test flakiness often stems from accumulated environment and configuration decisions, not randomness
• •CSS motion, feature flags, and optimistic UI states create hidden test branches that differ between local and CI
• •Make every environment setting that affects UX explicit in test configuration and capture full context on failure

Generated with AI, which can make mistakes.