The gadgets that make other gadgets aren’t making other gadgets anymore, either: MakerBot, a much-buzzed-about start-up that aimed to spark a 3D-consumer revolution, failed spectacularly to get people printing at home.

The gadgets that were Kickstarted have been Kickstopped, too. Pebble, whose first smartwatch earned a record amount on the crowdfunding site, failed to find long-term success in a category that would soon be overrun by big companies like Apple and Samsung. (Even other big companies had trouble here; Intel’s Basis watch was recalled after it burned its wearers.) Lots of other start-ups have raised tidy sums from crowdfunding sites, but the bloom has come off the rose; as often as not, the products are delivered late and don’t work as well as they should. Even if all goes as planned with the first gadget, the companies fail to translate onetime success into long-term stability.

Much of this isn’t a surprise. “Hardware is hard” is an actual phrase that people in Silicon Valley say to pass for wise. What they mean is, starting a company that makes physical stuff has always been more perilous than starting a company that just makes code.

That’s why the hardware market has recently been ruled by big companies, either as stand-alone businesses for the likes of Apple and Samsung, or as a kind of come-on for other services. Amazon makes devices like the Kindle and the Echo as an accelerant to its content businesses and its Prime subscription program. Google and Microsoft appear more serious about hardware, and they both might turn devices into nice side businesses. But neither sees hardware as a primary moneymaker; the devices are mainly ways to get us to use more of their software.

For start-ups, even in these days of easy contract manufacturing in China, gadgets involve a lot of costs — you need money for parts and a factory, and shipping and distribution, and you need virtually everything to go perfectly, because if your first gadget is a bust or has some fatal bug, you won’t have a lot of money to make a second one. And even if your gadget is a success, it won’t last long. The gadget economy is hits driven — you’re only as good as your next big thing.

And once you get a hit, you’ll get hit by cheap knockoffs. Just before I went on a trip to Hawaii last year, I thought it would be fun to get a GoPro camera to record some pool stunts. But when I searched Amazon.com, I noticed a ton of generic “action cameras” that carried many of the same specs as the GoPros, at a steep discount on price. I ended up buying an SJCAM for $75, about half the price of the cheapest GoPro I could find. And you know what? It worked pretty well.

This is the mixed blessing of cheaper manufacturing. “In some ways it’s much easier to be a hardware start-up than it ever was before, because the Shenzhen ecosystem gives you all the components you need,” said Jan Dawson, an analyst at Jackdaw Research, referring to the manufacturing hub Shenzhen, in southern China. “But that same ecosystem is available to everybody else, too, so setting yourself apart is really tough.”