When you sell a product in the millions, there's liable to be many thousands of units with some sort of manufacturing defects and they'll of course be overrepresented on this forum. If it were a widespread issue, we can usually tell from the many more posts reporting it like the crescent moon camera issue on the iPhone 6/6+, the iPhone 5 units arriving from factory full of nicks and scratches, and Antennagate. The number of posts reporting defective rubber gaskets and the back of the Watch case falling off hasn't quite reached that level.
Let me put it to you this way ...
I had a friend who bought one of the first Mercedes SUVs off the assembly line. He had a few warranty issues for which he took his truck in, and every time, they did about 2 or 3 other things he had reported no problems with. One time, they replaced the entire transmission under warranty, which he was having no trouble with, and which was totally unexpected. If he hadn't closely reviewed his work order, he would have never known, because they didn't tell him. This is not uncommon behavior for an auto maker. They issue internal recalls, which are quietly handled under the radar, before they become an issue, to avoid unfavorable public impressions during a product launch. And I make specific mention that it was a Mercedes due to the reputation of quality, reliability, and integrity, it shares along with Apple. That truck in particular is an apt comparison as it was a brand new first year, unique model, assembled at a brand new dedicated plant, using local labor. And I know Apple does this as well, addressing internal recalls when a unit is sent in for repair. The original Macintosh had one such recall which added a resistor array to the logic board, but only if a customer brought it in for other service, there were no customer notices otherwise.
My point is, where there's smoke there's fire. Who knows what other sorts of problems Apple may be aware of with the watch that may or may not appear over time? And who knows if Apple intended to original give it an IPX8 300m rating or not, but these manufacturing defects were too common to risk it? To me, this particular problem, isolated though it may be now, suggests yet another reason Apple may have given the watch a much more conservative IPX7 rating despite the fact in many casual anecdotal tests, the watch seemingly performs quite well. Yes only a few are coming out, and that may be all that ever do pop out. But how many would pop out, or otherwise fail if subjected to greater pressure from wearing in the water?
As for reported defects, while we don't know how many watches have been sold to date, we can be sure it took about 3 months before any significant volume were in circulation, and even now, it's unlikely the number of watches in circulation is any more than a small percentage of new iPhones sold. So I would argue there hasn't really been enough watches sold for any problem "gates" to materialize. Let's see where we are after the holidays (but even then, I would still assert, most of the likely potential problems have been mitigated by limiting its abilities).
