Uber and Lyft are betting on self-driving cars to become profitable. But that may not happen, new research from MIT suggests.

Uber and Lyft lose a lot of money.

Combined, the ride-hailing firms lost some $3.8 billion in 2019 alone, according to the companies' IPO filings.

Most investors, and many Wall Street analysts, are pinning the premise of ever turning a profit on self-driving cars. After all, paying drivers is a massive expense that could be all but eliminated with autonomous vehicles.