I recently went on a trip to the U.S. For 10 days I stayed in different hotels, and in each of them I wondered about the state of the power outlets...
Armed with an adapter for my German/European plugs I tried to charge the camera's or phone's batteries. I don't know if it's just me, but I expect to just plug a device in and get a firm and secure connection to the power outlet. At least that's what I am used to at home.
However in all the hotel rooms the sockets seemed to have no "grip" on the plugs which then tended to either slip out completely or at least lose contact all the time. I first thought it might just be the adapter model I brought, but even the lamps and TVs in the rooms had flaky connections which would easily slip out even when just brushing the cable slightly. I believe this may have to do with the fact that in the US system the power outlets are just flat while in Europe they recess into the wall and provide a much firmer mechanical hold on the plugs. The image is taken from German Wikipedia.
Maybe I am a little too "German" here, but I have to admit I felt really uncomfortable sleeping in a room with electrical connections like this. I have never seen such a thing here at home. If this is really normal, I wonder if there are more fires caused by problems with electricity in America than in Europe.