This document discusses the challenges of predicting the impact of SEO. It notes that predicting keyword volume and click-through rates is impossible due to constantly changing factors like news, user search behavior, and Google's algorithm. Specifically, it outlines how search volume can be impacted by external events and changes in how users search. Click-through rates are also difficult to predict due to variables like ad placements, device and location. The document concludes that while SEO metrics like rankings, traffic and conversions can be improved over time through testing and optimization, precisely predicting the impact of SEO is impossible given the many unknown variables that influence user behavior and search engine results.