Oppo’s Find X and Vivo’s Nex are the two most recent and exciting Android devices of the year. Why exciting? Well, they bring us closer to the dream of a truly bezel-less phone, and they do it in dramatic style. Instead of putting a notched area at the top of the screen, both of these phones hailing from China give us pop-up selfie camera modules. Vivo’s is like a miniature periscope, while Oppo’s elevates the entire top of the phone.

Just take a second to appreciate the fluid synchronicity between the on-screen animation when unlocking the Oppo Find X and the physical elevation of its slider. It’s a thing of beauty, hardware engineering meeting software design in a harmonious “whoa” moment:

There’s not a soul among The Verge’s staff who wasn’t wowed by this spectacular move. Jaded and bearded veterans of the consumer tech industry were suddenly amazed and amused by the clever mechanics of this new Oppo phone. As a showpiece, as a glamorous bit of brand flair, or a thing to show off to your friends, the Oppo Find X is an instant winner. When it hits store shelves, it’ll also be an immediately easier sale for shop assistants who can nonchalantly flick to unlock the device and then wait for the inevitable “what just happened?” reaction from the prospective buyer.

If this was the World Cup, Oppo’s Find X would be a Lionel Messi-like pirouette past three defenders, except it’d be going backward instead of forward. Adding mechanical parts to phones is a retrograde maneuver, which, in all honesty, creates a lot more issues than it solves. As a solution to the notch problem, especially, it is the equivalent of using a sledgehammer to crack a nut.

What’s wrong with mechanical sliders? I’m glad you asked. The issues are manifold. First, modern smartphones offer varying degrees of water resistance, but when you open up the phone’s innards like the Find X does, you lose that peace of mind. With glass on both the front and back — as Oppo uses on this phone and practically every other flagship smartphone is moving to — most people will want to put a case around their device, and the slider makes that tricky, if not entirely impossible. Dust, lint, sweat, and all sorts of other undesirable particles can get into the slider module. Ideally, you won’t be opening the Find X inside your pocket, but accidents happen, and I imagine that if you drop this phone with its camera slider open, it’ll be less structurally rigid than a unibody one.

Then there’s the biggest problem for my camera-loving self: with both the front and rear cameras hidden behind the display and inside the rear shell of the phone, there’s scarcely any space left to include a high-quality camera assembly. The reason the iPhone X and most of its best rivals have camera bumps is simple physics: the best imaging equipment requires depth to fit an array of lenses. Without wishing to sound too cynical, my expectations of the Oppo Find X’s cameras are not very high.

Two other factors weigh against the use of any mechanical components in modern phone design. One is power consumption: triggering that pop-up and pop-down motion may be cool as all hell, but it has an associated power cost. And given that there’s no fingerprint sensor on the Oppo Find X, you’re going to be using the selfie camera for face ID a lot during the course of a regular day. And the final matter is simple reliability. As noted designer Philippe Starck remarked back in 2009 when interviewed about the QWERTY slider Nokia N97, anytime you add a mechanical component, no matter how good or impressive, you’re making your product less durable. Apple has been on a mission to eliminate all its mechanical buttons, from iPhones and MacBooks alike, while HTC even went so far as to replace the side buttons on its U12 Plus with haptic-feedback touch keys.

I absolutely recognize the fun and superficial appeal of the Oppo Find X’s slider. It exhibits cohesive design that the Vivo Nex and other phones aren’t even close to, and it instantly adds a degree of character and uniqueness in a highly competitive but also homogenous Android flagship market. I don’t underestimate the tactile appeal of a mechanical part that moves in concert with the user’s whims, nor do I think the privacy reassurance of knowing all your cameras are covered up is an unimportant one.

And yet, I still see this as the past rather than the future of mobile technology. The smartphone is defined by its convergence of various tools and devices, by its shrinking of what’s necessary, rather than its expansiveness. I think Oppo’s goal was to wow us and pique global attention for its wares, which is why the Find X is so radically different. It’s a fantastic engineering showcase for a company with ambitions beyond its native market of China. The phone’s camera slider is also a cool retort to anyone clinging to the outdated accusation that Android device makers only ever copy the iPhone. But it’s not going to change the world or even the way phones are designed. It’s just a bad idea that’s executed well.