Radioactive decay provides discrete events, but the theory that models those events still assumes continuous time. The exponential decay law requires continuous probability flow, and smooth evolution of the survival function. Unless one accepts the Planck interval as the true temporal quantum, decay gives discretized outcomes embedded inside a continuous-time ontology. Bitcoin differs categorically: it does not measure time from an assumed continuum, it constructs time through irreversible, energy-expending events. Block time is not sampled from a continuous background but produced as the discrete unit of temporal ordering itself. In radioactive decay, discrete events are fitted to a continuous time; in Bitcoin, the events are the time. The real question is ontological: if time is fundamentally discrete, radioactive decay must be reinterpreted, whereas Bitcoin already embodies a discrete, thermodynamically anchored temporal structure without relying on any continuous substrate.