On the subject of electricity plugs/sockets - in my opinion the UK one has to be the most awful design of a plug/socket ever devised. It seems pretty clear that, on any of its perceived merits, it has failed to interest any other user nations apart from those where British interests are influential/decisive (possessions, colonies and ex-colonies, etc.). Look at two features: The metal contained in the lead versus the metal in the prongs of the plug (the plug is many, many times bigger than necessary), and the fuse (how many have a 13A fuse for a low energy lamp - who said safety feature. How absurd). I have personally had to replace sockets which permanently shorted out when the "safety" shutter spring came undone crossing live to earth. The fact that some devices are twice as big to incorporate the UK plug instead of the Euro or the US one is something else against it and I deliberately avoid the UK type whenever I can.
Conversely, what is the best design I have come across was late to the scene and also has not found serious favour over strong vested interests in the other designs despite probably being the safest. It certainly is the most attractive and it really is user friendly - the Ticino. I am no fan of the Schuko and its derivatives (French, etc.).