A faulty equipment poses a choice that does not end in the price of repair. It is necessary to consider downtime, availability of components and the ability of the good to carry out the required work. A replacement also involves start-up and adaptation.
I propose to distinguish the repairable problem from the overall conditions. An intervention can restore a function by leaving other criticalities open. On the contrary, replacing a still adequate good can commit resources without a proportionate benefit. Technical and safety assessments require appropriate expertise.
A hypothetical example is a device that needs a component available immediately. The choice can be different than an asset without assistance or with parts that are difficult to obtain. The comparison must include the necessary service during the scheduled standstill and future use.
The environmental profile also requires information: prolonging use avoids a replacement, but consumption and characteristics of the good can affect the overall outcome. It is not possible to always declare one of the two alternatives better. I propose to make explicit assumptions, costs and conditions, choosing on the basis of the case and verifying after the intervention whether the equipment actually supports the work for which it is maintained.