It can be difficult to explain to the boss why you need a second outage to replace a part you had in stock just prior to the first outage. How can you prevent a "we didn't know it wouldn't work" fiasco?
Before adding a replacement part to inventory, check the part number, size, and other identifying specs against your required inventory documentation.
Nothing goes into the stockroom without being properly labeled.
The storage area may appear to be dry due the absence of a roof leak (water ingress), but it can still be humid enough for spare parts to corrode. Consider using a dehumidifier.
When certain kinds of parts are received, temporarily put them in a holding area or on unapproved status. Add them to inventory only after completing pre-inventory assurance. For example:
Fuses. Visually inspect for damage (e.g., cracked body). Read the fuse indicator, or test with an ohmmeter (better still, test with a high-voltage resistance tester).
Motors. Manually rotate rotor, listen for grating, and test for runout with a dial indicator.
Critical circuit breakers. Conduct the recommended static testing or PM.
Critical cabling. Conduct insulation resistance testing, and record baseline data.