How can you streamline the maintenance process to minimize downtime in 3D printing operations?

Like with my shop CNC, I periodically check everything regardless. Part of this is logging the usage time at the check, the state of various bits, usually a bit anecdotal and guessy but it helps. Later I can use this to tell me practicable life spans for parts.

Personally, when I work with my FDM type 3D printer it is important to have a heated bed with good adhesion so that the first layer of plastic can adhere well to the bed, it is also advisable to always check the heated bed level, as in cheaper printers tends to become uneven after some prints, which causes an eventual failure in 3D printing, consuming plastic and the machine's operating time.

If I know a part only has x printing hours, or y meters of filaments in it, like a nozzle or heat barrel, before it becomes unreliable. I will check the hours and filament meters printed (thank you guys for getting this into most firmware and control software). If I find something beyond what I feel comfortable with, I'll just swap it out regardless, because a fail is nearly always worse to fix, and it is not nice to lose a print which can happen too.

Over time I've gotten an appreciation for what breaks. In the early days I kept several of everything, and my first prusa had nearly every part (except the frame rods) changed on it at least a dozen times before I retired it. Dont skimp, gets spares, if it breaks, make sure you have a spare in future... if you have tight lead times and dont like waiting on shipping that is (local prices always had ridiculous markup for me at least). Most of the parts I made on that printer, even did a PCB with a dremel very slowly.

Print racks are nice, to hold print platters full or fresh/ready. I used to have one for glass plates, but the new metal ones and self levelling is... obscenely decadent.

'Staff'.. hah, Have designed/built 30 printers personally. Have helped well over a thousand others build and get printing. even a Blind man, very proud of that, getting his screen reader to work with the comboboxes... we even got fixes to the software made. Very important to do this hands free, so they are the only one to touch anything. Get them to do a select few things at least twice infront of you too, so it sticks. It can be a wonderfully fulfilling experience, particularly with children. It does take serious discipline not to just take over. I dont do this anymore, afraid of harassment from HR vultures, over bizarre criminal conflict of interest claims.