Since the Oculus Rift first made waves with its successful Kickstarter, there’s been a consistent line of criticism based in the notion, “why would it work this time?”

It’s a fair question — you can go back decades and see myriad failed attempts to build virtual reality gear for the masses.

“Many very smart people have attempted to do this! What didn’t they see that Oculus and its compatriots see today? People didn’t want a Virtual Boy in 1995, why would they buy a Rift in 2015?”

That perspective misses one of the most important (and, almost always, obvious in hindsight) factors in tech: the actual technology that makes up a product.

Take a look at the actual pieces that, when put together in the right way, result in an Oculus headset. You’ve got a high pixel density LCD screen, a gyroscope and camera for positional tracking, and a 3D environment processed in real-time by a desktop computer or (in the case of the Oculus-compatible Gear VR, a phone!).

All of these things are only available at affordable prices to consumers thanks to advancements in other areas that have taken place over decades — specifically, smartphones and video games.

Was it possible for a hardware maker to build a display with a resolution greater than 1080p for a VR headset even ten years ago? Nope — it would have been prohibitively expensive for consumers and would use way too much power for portable devices to be a possibility without obnoxiously large external battery packs.

For instance, let’s say that to get the best experience in VR, your ~5.5-inch screen has to be 4K and refresh 120 times per second. In 2003, a screen with approximately that resolution would have run you $8,400, and would only refresh 12 times per second. Oh yeah, and it used as much power as a small desktop computer.

The current Oculus dev kit uses a 1080p screen from a Samsung Galaxy 3 and can refresh 75 times per second. The Gear VR uses the Galaxy Note 4’s 1440p screen. Progress!

Advances in real-time computer graphics are also key to providing a VR experience that’s compelling to consumers. While studies have shown that graphics don’t have to be “realistic” to provide a sense of presence in virtual reality, they do have to be smooth. Even a moment of graphics lagging behind input — in this case, moving your head to look around — can lead to serious motion sickness and ruin a user’s sense of immersion. The only thing you can do to about that is throw beefier hardware and smarter optimizations in code at the problem — things enthusiast hardware manufacturers and game developers have been working on for decades.

Those improvements happened outside of the context of virtual reality, but Oculus has packaged them in a way that has legitimized the field in the eyes of many investors and early adopters. There’s a new ecosystem emerging around building the interfaces and accessories that will make virtual reality truly mainstream, and it’s not just happening within Oculus HQ — or, as in previous decades, the confines of university research labs.

A Google search for “virtual reality Kickstarter” will turn up project after project building what could be the killer control mechanism for VR applications. If you go to a VR meetup or Oculus’s conference, you’ll meet an absurd number of developers working on what they think is the right way to do things, with ideas ranging from cameras mounted around the room to omni-directional treadmills and glorified Wii controllers.

Six months from now, those developers will know a lot more about what works and what doesn’t than they do now. The same can also be said for the past six months, and the year-plus before that since the Oculus hit Kickstarter. Things are in motion in the virtual reality space in a way that they simply haven’t been before.