Lack of inventory.
42mm Space Gray Sport shipping estimates slipped within 90 seconds of SOS. That's not demand. That's either A.) poor planning or B.) manufacturing problems.
Not to mention more luke warm reviews than I've ever seen for an Apple product.
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This was in response to:
"What evidence do you have that they are struggling?"
so when was the last time apple launched a product that didn't have supply issues?
One model out of many slipped to shipping 2-4 weeks after launch day. It sounds more like you didn't get your order in quick enough and are a sour.