Unexpected medal

[Lady Vulpix]

So, yesterday I decided to play White 2 for a little bit. It had been months since I last played. I did my round on the Royal Unova and then went to the nearest Pokemon Center and... the medal man was there! He gave me the "First Passerby" medal. Really, first passerby. Yesterday. I have no idea who that passerby was, nor where, when or how s/he passed me by. Nor why just now after I've been playing the game for years.

What do you think?

Have you received any similarly unexpected medals?

[Link]

I have many of them, but the one that stands out for me would be the defeating 100 trainers all at once in Black 2. That was an extremely hard medal to obtain.:)