Same underlying metric, same "more data is better" instinct. Drag the window below to change how much of the week you sample from, and where — then watch what happens to the distribution on the right.
Full trace — 7 dayshighlighted band = current sampling window
Sampling windowthis is the "zoom" — what you'd change in a metrics explorer
Selected window
Distribution of sampled values
More samples don't always mean "more normal." A 7-day window has ~10,000 points — far more than a 2-hour window — but it's almost always the worse choice here. It repeatedly crosses the same daily rise and fall, so the histogram just becomes a smoother version of the same two-humped shape. That's not noise you can average away; it's the actual shape of a metric with a daily cycle.
The 15-minute window fails for the opposite reason: too few points to say anything about the shape at all. The useful "middle" is a window long enough to gather a reasonable sample, sitting inside a stretch of time where the underlying process isn't shifting gears — not asleep at 3 a.m., not mid-ramp at 7 a.m., not straddling an incident spike.
In a monitoring console this is exactly why a wider time range or a coarser alignment period can make a chart look worse, not better — and why the fix is usually picking a more representative slice, not adding more of it.