Because, in a lot of peoples' minds, they make themselves obsolete with what something can do in the future, rather than what something does do now.Why is it obsolete? Why does someone else having something newer or better make your watch any less useful?
People seem to want Apple to make something and never improve any future versions so that they can feel like they have the latest and greatest.
I was a Microsoft Partner, and it was interesting how that old O/S that was the best thing since sliced bread, sucked when the new one came out. XP was when the customers started pushing back big time.