There is no merit in doing well what is not needed to be done. Reliability (Centered Maintenance ) is all about determining what must be done do keep assets doing what their owners need them to do under a specific operational context. Reliability analyses reveal how machinery components fail and recommend the necessary activities (including maintenance) to ensure they perform as intended to attain specific objectives. Reliability is a design characteristic, meaning that the more robust a component is the more reliability you can get from it. Maintenance, when performed correctly, ensures assets recover the reliability levels they gradually lose during their operation. Maintenance on its own won’t make assets more reliable than they originally were. Furthermore, unnecessary or wrongly applied maintenance would make assets less reliable and uncapable of rendering optimal value to organizations.