In maintenance there is a burgeoning sub-field in equipment health. The word maintenance means keeping an asset in a steady state and not allowing it to deteriorate. Health oriented sub-fields include TPM, PM, PdM, RCM.
The contribution of maintenance to the success of the enterprise is expertise in asset, machine and unit health. We are the folks who know what should be done for maximum life and minimum long term cost. We are the priests of the balance between production and equipment integrity.