The Apple way...

The Apple way...  The Apple Watch had a challenge.  Unlike any of Apple's previous products, a watch is perceived by many to be a fashion accessory or even a piece of jewelry.  That means that some customers will want the rich look of gold – preferably, a nice 18K gold as is traditional for watchmakers going back hundreds of years.  Probably any other manufacturer would simply have said “OK, make a gold model.”  Apple noted, however, that traditional 18K gold has two problems.  First, it's expensive, especially when gold is going for $1,200+ an ounce.  Second, it's relatively soft – though 18K gold is much harder than 24K gold, it's still soft enough that it's easily scratched.

So Apple developed a new kind of 18K gold (see this explanation) that uses less gold and is more durable.  Very clever, that.  Also a great example of what can happen at the conjunction of visionary product development, scale, (almost) unlimited funding, and total vertical integration...