When I moved to the Midlands many moons ago one of my first jobs was at a Tube Polishing company. Basically I stood at a machine and fed tubes down it all day every day till they were sparkly bright. The 'Gaffers' hated the machines being idle but sadly they had to be turned off so they could be cleaned of swarf every day, the thing could get clogged up or even possibly catch fire if not. The Gaffers would pace up and down looking at their watches yelling "Come on, come on!"
Today we are fitting a graphics card to a PC at one of our customers, the conversation went as follows:
Customer: "So how long will it take?
Me: "Umm? 15 - 20 minutes? Basically we have to shut it down, take the side panel off, remove the blanking plate, fit the card, put the side panel back on, start the PC, probably install the drivers. TBH it might not even take that long but I'm allowing for any problems."
Customer: "Hmm? OK, we can live with 20 minutes I suppose?"
Have I walked through a worm hole and been transported back to 1986?