To maximize their revenue, publishers have tons of puzzles to solve on a daily basis. Besides big picture goals like maximizing CPMs and increasing competition for their impressions, a lot of time and work goes into clearing ad stacks from low-quality bidders, reducing latency, and preventing malicious popup ads. It's essential work: Daily pursuit for quality improves the user experience, increasing page views and preventing money from slipping through the cracks. However, ad stack optimization is much more daunting than it sounds. Its success directly depends on ad auction data (its recency, quality, and availability). If you don't know how your ad stack is doing, how can you know if adding a partner or tweaking a floor helps or hurts you? Collecting data, processing, and analyzing it are big challenges that most publishers haven't solved yet. It's not easy; the data's fragmentation, industry giant's walled gardens, and middlemen's data black boxes are all huge obstacles.