Why do wizards - particularly in MoR, where most people are smarter - carry one wand apiece? This doesn't seem to be an absolute practical limitation wherein only one wand may be mastered at a time. In book seven, Harry is simultaneously the master of the Elder Wand and his own original with Fawkes's feather in it. Why doesn't everyone habitually walk out of Ollivander's with two, so as to have a spare in hazardous situations or in case one should be lost?
We know that, in a pinch, you can use someone else's wand. But can you use nobody's wand?
Maybe the wands are intelligent enough that they don't fully activate (although they will still do testing waves) until after they choose a wizard, but stupid enough that they'll let anybody use them once they've been activated.
We also need a rule to deactivate the wand after its wizard dies, although a tradition of burying a wizard with their wand might be enough. There could be a black market in used wands, but as long as it's small, most people will still only have one.
ETA: There is now a third thread, so send new comments there.
Since the first thread has exceeded 500 comments, it seems time for a new one, with Eliezer's just-posted Chapter 33 & 34 to kick things off.
From previous post: