I dunno. I've never had a throw-it-away mentality. Got that from my dad, I think.
My main darkroom timer is an ancient GraLab Model 168 stamped as having been manufactured during, I believe, the Eisenhower administration. Got it as a hand-me-down.
It contains a very simple synchronous timing motor. I opened it up and let the entire motor/gear assembly soak in some acetone to strip away any old dirt and goo. Then I put it back together and gently lubricated a few points with some machine oil. Turned it on and it started right up.
It has worked without any problems now for years. Matches my RF-set quartz wristwatch perfectly. I even use it to adjust the internal calibration of my Zone VI Compensating Developing Timer both for real time and compensated time.
I once visited the majestic Grand Coulee Dam in Washington state. During the tour an engineering fellow described the painstaking procedures they used to bring generators back online after maintenance cycles. They feather them in very precisely because they are aware that there are a large number of synchronous timers still out there, and they don't want to mess them up.