Anna Heiermann discusses lessons learned from past testing failures and advocates for a risk-based testing approach. A risk-based strategy involves identifying product risks, prioritizing test cases based on risk, and communicating the test plan to stakeholders. This helps ensure the highest priority and most critical areas are tested thoroughly. When risks are missed, it can lead to catastrophic bugs affecting users and lost revenue. With a risk-based approach, testing is targeted efficiently to reduce risks while keeping stakeholders informed.