Hazard Rate Theory
The instantaneous failure rate h(t) describes the conditional probability of failure in the next instant, given survival up to time t.
Infant Mortality
The failure rate is high initially but decreases over time. This indicates early-life failures due to manufacturing defects, installation errors, or material flaws.
Random Failures
The failure rate is constant. The asset does not "age" in a reliability sense; a component that has survived 10 years is just as likely to fail in the next hour as a brand new component.
Wear-Out
The failure rate increases over time. This indicates components degrading due to fatigue, friction, corrosion, or simple aging. Preventive maintenance is highly effective here.