Better designed? You can plug an grounded plug into an ungrounded socket and there are many ungrounded plugs that won't go into grounded sockets.

In the UK (exclusively, I think), the sockets have gates - in [1] you'll see that there's a lever in the top hole - that pushes down the plastic covers in the bottom hole allowing the pins to be inserted. The earth plug is longer than the live and neutral plugs, meaning that you cannot electrocute yourself with a plug unless you really try. At the same time, plugs [2] typically have plastic guards around most of the pins, such that no electricity can be flowing through the pins while it's exposed.

Of course, it was all for nothing when as a kid I put a braddle or something in the top hole and then mucked around with the bottom hole. Also, I imagine that the foot injuries you get in the UK are also greater because the plugs typically face up (although I've only seen someone actually impale their foot on a holiday in America). But yes, we have the safest sockets in the world according to my old schoolteacher.

[1] https://upload.wikimedia.org/wikipedia/commons/d/d4/Uk_13a_d... [2] http://img.diytrade.com/cdimg/533618/3871293/0/1182923133/Br...

The UK is an anomaly when it comes to plugs and sockets - the very fact that almost(?) every plug has to have its own fuse is a tell.