Quantitative (ie telemetry) data gives us the what, not the why. Qualitative (usability testing and other observation methods up to and including ethnography)

Quantitative (ie telemetry) data gives us the what, not the why. Qualitative (usability testing and other observation methods up to and including ethnography) can give us the why (users seem to do what we didn't expect). Modern UX design can make use of both modes of user research such that they support each other. I.e discover the what via quant and understand it better via qual, to land at a solution. Or discover both why and what via qual, and then determine severity (how many users get stuck in a given way) via quant. But of course, there needs to be explicit consent such that trust is not breached, no matter how inconsequential the data collected is considered to be. The decision belongs to users. Apparently there wasn't consent. Edit: Ideally, should anonymised usage data in OSS projects be public? Such that we can see the data and design decisions made based on it? Perhaps this would generate more of the trust that was desired here.