You are managing an engineering team delivering features for a B2B SaaS product, and leadership wants you to use delivery metrics more consistently to improve execution. Over the last 3 months, average sprint velocity increased from 38 to 46 story points, but median lead time from ticket creation to production release also rose from 9 to 14 days, while escaped defects increased from 11 to 17 per month. The team also introduced a new code review policy and shifted 20% of capacity toward platform work during the same period. You need to explain whether the team is actually getting more effective or just appearing more productive.
How would you use metrics such as velocity and lead time to evaluate team performance in this situation, and how would you diagnose what is driving the conflicting signals before deciding what changes to make?