Barring unforeseen weather issues or other problems, SpaceX will launch its Falcon Heavy rocket with an onboard Arabsat-6A communications satellite at 6:35 p.m. ET on Wednesday. For Elon Musk’s space transportation company, this is a chance to prove that its most important rocket is capable of helping it fulfill its most important missions.

It will also be SpaceX’s second ever Falcon Heavy launch, and the first time the rocket will be used for commercial purposes. Then, when the ascension is over, it will also be an opportunity for SpaceX to successfully land the Falcon Heavy’s two side boosters and center core back on Earth—something that evaded the first launch after the core missed its target.

Launching and landing a rocket aside, the Falcon Heavy event represents several make-or-break matters for SpaceX. Here are the three biggest reasons why this launch will be the company’s most critical mission yet:

Its Falcon Heavy’s audition to be a money-maker

The stakes were high when the Falcon Heavy lifted off for the first time in February 2018. The Falcon Heavy is the most powerful rocket in the world, a necessity for bringing payloads to space successfully.

At the time of its launch, SpaceX chief Elon Musk said he wasn’t sure how the start would go or whether it would be successful. All eyes were on the sky. Luckily for Musk and SpaceX, almost everything went off without a hitch.

The Falcon Heavy took off, brought a Tesla to space, and despite the core stage missing its target on its way back to Earth, the mission was a success. Soon after, lucrative government contracts rushed to SpaceX.

However, in the space game, you’re only as good as your last launch. Moreover, thanks to the Arabsat-6A, which will be used to beam communications services to the Middle East, Africa, and Europe, this is the first time that SpaceX will have Falcon Heavy’s commercial chops on display.

If the launch goes well, there’s a good chance other companies and governments will be lining up to hitch a ride on a future Falcon Heavy launch. If the launch goes poorly, it could be a significant setback to SpaceX’s fledgling Falcon Heavy business.

SpaceX’s business model depends on sticking the landing

The issue with traditional rocket launches is that they’re very costly. That’s due in large part to their lack of reusable components.

SpaceX has built its business around reusing the boosters and center core that help to propel the Falcon Heavy into space. The boosters and the core go up with Falcon Heavy but float back down to Earth at specific points during the launch. The components are supposed to land intact to be reused in future launches, in order to keep costs down.

And keep costs down the parts do.

According to Space.com, Falcon Heavy flights cost SpaceX customers between $90 million and $150 million. Falcon Heavy’s closest competitor, the United Launch Alliance’s Delta IV Heavy rocket, costs $350 million, according to CEO Tony Bruno.

Pricing for space transport on Falcon Heavy are in part predicated on successfully landing reusable components. Now, all eyes will be on Wednesday’s launch to see if SpaceX can successfully land those boosters and core—and prove its business model.

If successful, Falcon Heavy could take SpaceX to Mars

As lovely as government contracts might be, SpaceX’s ultimate goal is Mars. The company hopes to get there on the back of the Falcon Heavy. But before that can happen, plenty more work needs to be done. Most importantly, SpaceX needs to have more successful launches.

Any glitch in the Falcon Heavy’s track record could cause a wrinkle in SpaceX’s Mars plans. Also, depending on how big of a hiccup Falcon heavy potentially suffers, it could call into question whether a human flight to Mars is even possible.

None of this means you shouldn’t bet on SpaceX. The company did not respond to Fortune‘s request for comment, but the truth is it has been successful at exceeding expectations at nearly every stage. The stakes are high and the risks great. A single misstep could be a problem for SpaceX. Then again, that’s no different from every other launch.