In nearly 40 years of work in a variety of industries and job positions, I can honestly say there was never two weeks in a row similar in time distribution among those activities.
I can recall literally months at a stretch where I never had to fight a fire; and some periods where 100% of my time for two or three weeks (12 hour days) were engaged in firefighting.
Of the firefighting, roughly half were avoidable in hindsight. The other half, though, were such complete surprises that even in hindsight, I don't see any possible way I could have reasonably planned for those contingencies.
Remember, this is from a guy who was obsessive throughout most of my career about "being prepared" and setting up failsafes to avoid fires.
Here's one example of a surprise fire that took up an entire two weeks of my life 12 hours/day, 7 days/week:
At our aerospace company, we hired a subcontractor with vast experience in making aircraft "black boxes" for military planes to make some junction boxes for one of our systems to be installed in yet another aerospace manufacturer's system for final installation in commercial aircraft.
I "babysat" our supplier daily throughout the manufacture and oversaw final electrical conductance tests at various points on the box. I was absolutely satisfied with everything.
We did our part of the installation and I was similarly satisfied. When we sent the finished subassemblies to the next supplier in the chain, they started bouncing with "griefs" (the customer's jargon for a nonconformance.)
Everyone went into overdrive. We tested the boxes being returned for the suspect electrical "leaks or impedances and couldn't duplicate the readings our customer had found. We went to our supplier and used his equipment and we could not duplicate the finding. We called in a testing lab and they, too, were unable to find the same reading as our customer.
After a flurry of suspicious finger pointing, we got down to the ohmmeters we were using and involved Fluke (who manufactured ALL the meters in the case.) After 48 hours of hemming and hawing, we finally got an engineer at Fluke to explain that the various characteristics of the meters involved were not equal, despite the product brochures reading otherwise. Using more sensitive Standards and new meters supplied by Fluke, we were finally able to replicate the readings - end of week one.
Week two involved tearing down 160 subassemblies worth 30 thousand each to try to find the cause of the impedence. The ultimate cause turned out to be contamination from a dielectric caulk used on open threads of machine screws protruding into the box to keep them from abrading the insulation on the wire bundles inside. The assembler at our subcontractor had the faintest smear on her static and lint free gloves. She touched the contact points where connector cables were to be attached, creating an electrical conductivity barrier on just a few of the 160 boxes in the original shipment. Some days during assembly, she started with fresh gloves and the first few assembled would be OK. Sometimes she went back to check some of the first of the day once her gloves had been contaminated. The glove contamination was invisible to the naked eye. We smeared the glove on a glass plate and had to look at it under ultraviolet light to see the smear.
My lips are still raw from all the butt-kissing I went through to salvage the contract.
Tracing the contamination meant checking every possible source of dielectric compound or loose wiring or faulty silver or gold plating on contacts, then determining how or where it contaminated the product. The fix was incredibly simple - mistake proofing the application of the caulk (absolutely necessary to the box according to the engineers and FAA) until AFTER all electrical connections were made as the final step prior to closing the box. Plus we learned a lot we hadn't known about multimeters for dealing with measurements to the thousandth of an ohm.
Still, I will give it a shot, but it is an exceedingly rough estimate, (and the categories overlap a great deal):
