Flat sheetmetal is the hardest to fabricate - and keep flat! There is a reason old cars were rounded.
When I was a student at GMI, one of our professors was talking about sheetmetal working and explained why the cars of the 1930's through the 1950's all had round, bulbous looks to them. If you stamp sheetmetal in a curve, it is actually stronger than it would be when flat, and will hold its shape better. Best of all, it won't "oilcan" on you - a problem with flat metal that occurs when the metal bounces between two equilibrium states.
You've seen it before. In a stage play, they shake a piece of sheetmetal to simulate the effect of thunder (not convincingly, to me). I had a friend who loaned his Cadillac SUV to a pal, who promptly backed it into a ditch. They had it repaired, but it was never the same. The rear roof panel (flat) would "oilcan" every time they went over a bump, making that characteristic noise - and it is almost impossible to fix.
In the late 1950's, car makers started doing "deep draw" stampings to make tail fins. They pushed the sheetmetal art to the limits. Of course, back then, "body lead" was used to fill in seams (such as where the roof met the "C" pillar) and a lot of cars had a lot of lead in them. Chrysler Imperials famously had no body seams - they were filled with lead. By the 1970s and 1980s, the "square" look came into vogue, and this created challenges for Engineers. Large flat sections of sheetmetal would tend to oilcan, so they put creases and folds into the body to prevent this. Even so....
I went to work at Carrier in the air handling lab, where we built and tested prototype air handlers. These were big sheetmetal boxes with a big fan in them (and a coil). To keep them from oil-canning, we would cross-break (or cross-buck) the sheetmetal. Later, we devised a method of embossing ribs in the metal, which allowed us to use thinner metal. You see this technique used on things like "Jerry" cans used to hold gasoline on the back of a jeep. Ribs strengthen the metal, much as cross-breaking does (only better).
So, anyone who has tortured sheetmetal, as they used to call it at GM, knows that making a vehicle with nothing but flat surfaces is bound to be trouble. The flat panels will "oilcan" unless you make them really thick, which is too heavy and expensive, or back them with ribs or embossing them. Moreover, it will be harder to maintain dimensional stability with flat panels, making door and hood seems look uneven.
Tesla announced its childishly named "Cybertruck" years ago, in a product announcement famous for Elon Musk breaking the "unbreakable" windows. It was fortunate they were breakable, as an unbreakable window could trap passengers inside, if the vehicle caught fire (which of course Teslas never do). He touted the truck as having an "exoskeleton" when in fact, it was just a typical unibody - something pickup truck buyers would avoid (other than perhaps, the Honda "pickup" which even has a fake body seam in it to make it appear the bed is mounted to a frame, when in fact, the "truck" is based on the Odyssey minivan).
The truck has been delayed for years now, and in the meantime, Rivian has started production and sold trucks (I have seen several on the road now) and Ford and GM are offering electric versions of their standard pickups. Why Tesla is late to market is a good question, but a recent Tweet on TWITTER from Musk hints as to why. He claims the truck looks like crap as the flat panels don't meet up well and minor imperfections in flat sheetmetal show up more easily. Any Engineer coulda toldya that.
His solution? To make the sheetmetal in tolerances higher than used in ball-bearings. It is a ridiculous Tweet as any Engineer could tell you that the staggering cost of making body panels to instrumentation specs is a pointless waste of money. Just add some creases or curves, and the panels will look good and fit. Flat panels - even if you could make them to micron tolerances, would be a nightmare to repair, even for the tiniest of dents.
But maybe this is just an excuse to delay the production of the "Cybertruck" indefinitely - while shoring up the stock price. Know-nothings on the Internet buy Tesla stock (and AMC and Gamestop) and tell each other the price will keep going up. I saw one posting online claiming that AMC stock will go up to $1000 a share, when it is languishing at $12 right now. There is no secret sauce or "moat" to running movie theaters, which are a dying brick-and-mortar business anyway. But that didn't stop them from being patsies in a grand pump-and-dump.
Similarly, Tesla stock was hyped to the stratosphere and is finally coming back to Earth. The "World's Richest Man" was rich only on paper, and he blew most of that buying TWITTER. I saw a posting online from a fan-boy showing the "Cybertruck" leaving the Tesla factory, behind a Model X. "See?" he said, "It's in production already!" In fact, it is not. But you see how they spread these rumors to prop up the stock price.
Worldwide, we see this nonsense. Evergrande is trading again and lost 80% of its value overnight. Entire cities of empty buildings have been built in China, and no one actually lives in them - they are the tulip bulbs or crypto-currency of condos. And the longer this bubble goes on, the worst it will be when it bursts - and it is bursting now. Similar bubbles are happening in the USA and in particular, Canada, where housing prices have reached ridiculous proportions for no apparent reason (although Chinese buyers are one aspect of this, yet again).
Frankly, I am shocked that newbie Rivian is actually selling pickup trucks before Tesla. But I think Rivian may be in for a rough time if the economy declines. As I noted before, I am getting flooded with e-mails from every retailer I have ever done business with begging me to buy more "stuff."
I see a slap of reality, 2008-style, coming around the bend. The longer people want to believe in fantasies, the worse it will be. Putin believes he can take over the world - and yet half his army has been destroyed, using surplus equipment various Western countries have sent to the Ukraine. MAGA-hats think that Donald Trump is some sort of financial genius who will "save America" by turning it into a totalitarian State ("FREE-DUM!" - ironic, isn't it?).
We are due for a wake-up call. The alarm keeps going off, but we keep hitting the "snooze" button and go back to dreaming - for just a little bit longer.
UPDATE:
Note the duct tape covering the panel gaps. Note also the awkward transition to the windshield frame - like a DeLorean someone made in their back yard. Notice how the driver's door panel is oil-canning. What a mess. A few creases or body lines would fix a lot of this. The rest of it looks just as bad.
