Percentiles without provenance are soft fiction
p99 is only useful when you know which routes and releases fed the bucket.
Leadership loves a single latency number. Engineers know that number mixes cold starts, partner spikes, and a deprecated mobile client that still ships.
Traffic intelligence work asks for provenance first: which routes entered the percentile, which releases, which consumers. Without that, capacity planning becomes negotiation theatre.
Our Kwai Tsing desk treats provenance as a deliverable—not a footnote—so the next release can defend its own slice of the graph.