maintain : to keep in an existing state (as of repair, efficiency, or validity) : preserve from failure or decline — Webster
Maintenance involves functional checks, servicing, repairing or replacing necessary aspects of something. Over time, this has come to include multiple wordings that describe various cost-effective practices to keep things operational; these activities occur either before or after a failure. — Wikipedia
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Process, Manage, Design, Prototype, Implement, Assess, Revise, Maintain