The automotive world has long gotten used to misleading concept cars that end up disappointing everyone. It's one thing for these models to look amazing in a showroom and boasted about in a press conference. It's another for them to work. Many cars were intended to be terrific, but things just went wrong in production. Other times, the companies gussied up the concepts to make them look better for the public. Either way, car companies have learned the hard way that hyping up cars can often backfire.

It's easy to look at cars that become massive flops, but there are also cases where the final product wasn't too terrible. It simply wasn't as great as the company had promised, so come off lacking. But others are just horrible in huge letdowns from the fantastic cars that could have been.

Here are ten notable cases of vehicles that failed to live up to the company's promise and why it's so easy to distrust a cool concept making it to the streets.

10 The Trans Sport Was Sacked

home1.info

Few vehicles have been such a massive letdown from concept to production than the Pontiac Trans Sport. When it debuted in 1986, Roger Smith boasted this was the van of the future. It sure looked amazing with lift-up doors, a glass roof, and even integrated video screens.

1986 Pontiac Trans Sport Concept: Lost In Translation
via Pinterest

In so many ways, it was ahead of its time...in concept. The actual Trans Sport was like any other minivan sans all those cool features and a bad engine. The idea was beautiful, but there was nothing sporty on the final product.

9 The Sunfire Didn't Shine Brightly

As bad as the Aztek may be, the Sunfire is actually one of Pontiac's worst efforts. First, Pontiac boasted about this being a "brand new" car when it was really the ancient J-body frame.

1990 Pontiac Sunfire Concept: Killed The Sportiness
via Pinterest

Imagine a Cavalier with plastic paddling and an engine barely getting 120 hp. It rated horribly in crash tests and lacked the styling shown in the concept form. It didn't take long for the sun to set on a car that began Pontiac's slow fall.

Related: 10 Craziest Concept Cars Of 2020

8 The 2002 Thunderbird Disgraced Its Legacy

2002-ford-thunderbird
via bestcarmag

Thunderbird fans may debate what the best model/year is. But when it comes to the worst, there's little argument. In 2002, the Thunderbird was brought back with talk on how it would be the best one ever with a powerful engine mixing classic muscle charm with modern technology.

The Eleventh-Gen Ford Thunderbird
via Pinterest

But the V8 only produced 250 hp, not nearly enough to power it to great levels. That's without a design that looked like a typical sedan rather than a muscle car. The worst part was the outrageous price tag that made the Thunderbird an epic flop.

7 The Plymouth Prowler Didn't Roar

Plymouth Prowler
via driving.ca

The Plymouth Prowler sure had the fabulous looks of a retro-roadster. It's wild but stands out with a fantastic design that makes one want to drive it. Sadly, once it did, it was a complete letdown.

Plymouth Prowler
via mecum.com

Instead of a mighty V8 to power this monster, it was a 3.5-liter V-6, so while the 225 hp was good, it couldn't live up to the concept model's promise. It's notable how Prowlers with a V8 perform so much better, so had Plymouth made it that way from the start, this could be a modern classic.

Related: These Cars Are Ugly As Sin...But We'd Buy Them

6 The Volt Had No Spark

Chevy Volt
Via wired.com

The Volt's legacy is tied into one of the single worst marketing campaigns of all time. The infamous "Volt Dance" made the car look like a joke from the start, but it was even worse than folks imagined.

2007 Chevrolet Volt Concept: From Muscle To Weakness
via Flickr

The concept was a four-door Camaro that would get 140 miles to the galleon and an all-electric range of 40 miles. What came out was a lame sedan with a top speed of 100 mph lacking much style. The range wasn't bad, but the Volt just didn't spark as promised.

5 Jaguar Cheaped Out On The XJ220's Engine

Via Thetruthaboutcars

Jaguar doesn't have many misfires in its history, but this was a doozy. When the XJ220 was introduced, folks were excited, not just for the sleek style but also for the fantastic V-12 engine, making it one of the fastest cars in the early '90s. When customers finally started driving, they were confused about the lack of major performance.

Jaguar XJ220
via Motor1

That's because the production model had a turbocharged V6 to make it one of the few times a 220 mph car can be labeled a "disappointment." Had Jaguar lived up to the V12 promise, this car would be legendary.

4 The DeLorean Wasn't Very Futuristic.

wsupercars.com

All of the wild things in Back to the Future, making the DeLorean look like a cool car may be the most fanciful. John DeLorean promised big things with a rustproof stainless steel body, gullwing doors, and an engine to make it one of the best sports cars around.

dmc-delorean
via topspeed

What owners got was a 2.8 liter V6 for barely 109 mph top speed. It enjoyed a cult following thanks to that movie when the real DeLorean never came close to its promise.

Related: We Wouldn't Drive These Classic Cars If You Paid Us

3 The EV1 Wasn't The Game Changer Promised

The common story is that the reason the EV1 failed was that some evil oil companies and competitors united in crushing it. The reality is that the first major electric car simply wasn't that good. Back in the mid-90s, the tech wasn't there to make it work properly as it only had a top speed of 80 mph and the battery range was only 70 miles.

GM declared this would start a revolution for electric cars, but it took decades for that to become more popular with the EV1, a quickly ended flop.

2 The Chevrolet SSR Was One Of The Worst Pickups Ever

Via Car & Driver

Maybe, on paper, the idea was sound. It's not like there haven't been odd ideas for a pickup truck, so a convertible really wasn't the worst ever. But in execution, the Chevrolet SSR made just about every mistake imaginable.

2006-chevrolet-ssr
via topspeed

Instead of a hot rod engine was a 5.3-liter, 300-hp V-8, which was weighed down by having it be a pickup. The handling was also poor, and it was way too expensive for pickup owners. The SSR could have been something unique instead of dying out fast.

1 The Aztek Flopped Majorly

1999 Pontiac Aztek concept car
Old Concept Car

The Pontiac Aztek has seen an odd second life thanks to being featured on Breaking Bad. For some reason, this makes people believe it was a good car when it wasn't. This is a car whose auto show debut had Don Butler body surfing a mosh pit. Amazingly, it was conceived as "GMC Syclone with off-road tires."

Instead of an SUV-sports sedan, it was a minivan crossed with a worse minivan. It's a punchline to countless jokes and astounding to see how anyone can like this vehicle's mess.

Sources: jalopnik.com, autotrader.com, caranddriver.com, thetruthaboutcars.com

Next: These Cars Are Expensive But The Interiors Are Cheap