Customer: *hands me a printer* "Is this all I need to print? My last printer broke."

Me: "No, ma’am. You still have to purchase ink and a printer cable for it."

Customer: *grabs random ink off shelf* "Okay, here we go."

Me: "You have to get the specific brand and number listed on the box."

Customer: "Oh, well, normally you can just mix and match. I’m new to this web 2.0 nonsense but I think I know a little about setting up a printin’ machine!"