Tesla's Cybertruck is finally starting production, 2 years behind schedule. Here are 6 other projects Elon Musk promised to deliver by now.

• Tesla's Cybertruck is finally beginning production, two years behind schedule.
• Tesla CEO Elon Musk has been known to make lofty promises that can take years to be delivered.

It's safe to say Elon Musk doesn't have the best track record when it comes to delivering on his promises — just this week, Tesla finally began production on the Cybertruck in its Gigafactory in Texas, four years after releasing its prototype and two years behind its planned production date.

The electric truck isn't the only thing the Tesla CEO promised that was late or undelivered. Here are six other projects he has yet to bring to fruition.

Fully self-driving Teslas

In 2016, Musk set a two-year timeline until Tesla users would be able to use the "summon" feature — still in beta mode in 2023 — to have their car drive autonomously to them from anywhere connected by land. Inverse reported that Musk expanded the promise in 2017 when he assured buyers that it would be just two more years before self-driving Teslas could be used to travel cross-country while passengers sleep.

Teslas currently use "autopilot," which the company defines as an "advanced driver assistance system." However, Tesla says drivers must be "fully attentive," have their hands on the car's wheel, and be "prepared to take over at any moment." Features like traffic and stop-sign control are still in beta and also require driver attention to be safe, Tesla says.

One million robotaxis

On Tesla Autonomy Investor Day in 2019, Musk said that Tesla would have more than one million "robotaxis" on the road in 2020, reported CNBC.

"I feel very confident predicting autonomous robotaxis for Tesla next year," Musk told investors, according to CNBC. "We won't have regulatory approval everywhere, but I am confident we will have at least regulatory approval somewhere, literally next year."

His plans for ride sharing or "taxi" Teslas were first suggested in 2016 in his "Master Plan, Part Deux," in which he said autonomous Teslas could be rented out when their owners were not using them.

Today, there is not yet a single robotaxi in use.

Hyperloop systems

Musk first introduced the idea of a Hyperloop system that could move up to 760 miles an hour in 2013.

In 2017, he tweeted that he had "verbal govt approval" for a Hyperloop connecting New York, Philadelphia, Baltimore, and Washington, DC — a track he said would take users from New York to DC in 29 minutes.

However, Musk's The Boring Company removed plans for a DC transit tunnel and a tunnel in Los Angeles from its website in 2021. In October last year, The Verge reported that the Hyperloop Musk was building in Southern California had been replaced by parking spots for SpaceX employees.

X, the "everything" social-media app

Last year, Musk tweeted that his purchase of Twitter was an "accelerant" to the creation of X, the "everything app." He estimated Twitter would speed up X's production by three to five years.

What exactly the "super app" might be remains unclear, though Musk has cited inspiration from WeChat and referenced plans to build the app on a blockchain system. He also pledges to emphasize free speech, battling fake users run by bots, and potentially a subscription model, like Twitter Blue — interesting goals for Musk, given that just days after he declared comedy "legal" on Twitter in November 2022, he suspended accounts using their free speech to make fun of him, according to reporting from Time.

Musk also previously failed to get rid of bots on Twitter, instead blocking legitimate accounts and "huge" carriers using faulty content-moderation tools.

Production plans for the app, though, remain nebulous.

SpaceX taking CO2 out of the air to make rocket fuel

Musk tweeted in 2021 that SpaceX was starting a program to convert carbon dioxide from the atmosphere into usable rocket fuel.

"Please join if interested," the tweet continued. "Will also be important for Mars," a subsequent tweet read.

There have not been any updates on the program since, even though the technology is possible and being developed by researchers, including those at the University of Cincinnati.

Production of 1,000 solar roofs a week

Musk also said he would install solar panels much more rapidly after Tesla's 2016 acquisition of SolarCity, a solar-installation company run by two of Musk's cousins, CNBC reported.

"Spooling up production line rapidly," Musk tweeted in July 2019. "Hoping to manufacture ~1000 solar roofs/week by end of this year."

CNBC also reported that Tesla installed an average of only 21 solar-system installations a week in 2022, its most productive year. In the first, most productive quarter of 2022, peak installation averaged only 32 roofs a week — which means that at its highest productivity, Tesla installed just 3.2% of Musk's goal.

Tesla did not immediately respond to a request for comment sent outside regular business hours.