Even the best-planned campaigns can hit bumps. Costs rise, conversions fall, and stakeholders start asking questions. This chapter is about diagnosing problems quickly and applying fixes that actually work.

Key Points:

• Always diagnose before reacting: check that tracking is still working, nothing has changed in your setup, and look for macro factors like seasonality or competitor moves;
• A drop in CTR usually points to creative fatigue, poor ad relevance, or irrelevant search terms;
• Rising CPCs can come from more competition, a bidding strategy change, or declining Quality Scores;
• Falling conversion rates often signal landing page issues: slow load speed, poor mobile UX, or misaligned messaging;
• Low ROAS may be caused by wasted spend on low-value conversions or a misconfigured product feed in eCommerce;
• Prioritize fixes by impact: Tackle fast wins (like pausing underperforming ads) while planning long-term improvements (like redesigning UX);
• Communicate findings clearly and test one change at a time to avoid guesswork.