I see there is the [`CachedGauge`](https://dropwizard.github.io/metrics/3.1.0/manual/core/#cached-gauges) in the DropWizard Metrics (formerly Coda Hale Metrics) lib. I'm wondering why anyone would *ever* use this?!?

My *understanding* of the value of a metric is that it is real-time, accurate and relevant. If a metric is reporting a stale/cached value, of what purpose could it possibly serve?