Documentation sources indicate discrepancies between deliverability data platforms like Google Postmaster Tools (GPT), Microsoft SNDS, and third-party providers stem from variations in data collection, scope, and methodology. GPT offers aggregated, anonymized data on Gmail traffic, while Microsoft provides data specific to its users. RFC Standards clarify Feedback Loops (FBLs) report spam complaints, but implementation accuracy varies. A comprehensive assessment necessitates utilizing a mix of tools, like MXToolbox, to monitor email health aspects beyond spam complaints, such as blacklists and DNS settings.