you realy think 10 minutes is laughable?
think about it. we are talking assembly lines here. all components laid out. PSU with wiring the correct length. no little single single switch front pannel wireing. more snaps and clips than screws. no custom wire routing. 10 minutes to slap together a PC is very doable, even more so if you doing the same thing over and over and not being overly carefull. heck, they don't even mess with thermal compound, just the thermal pads. when I assemble a PC, most of the time is spent reouting the wires all fancy like, and digging for the correct screws.
clip in the CPU + heatsink and memory. 8 screws to hold down the mobo. 4 screw for the HDD. spap in optical. snap in the graphics card. plug in the front pannel, 2 satas for drives, power cords for mobo, cpu, 2 drives, gfx card. and a fan or 2.
you really think that takes more time than an oild change and vehicle inspection?