Anyone following the saga of Uber and Lyft knows that mobility services are not - not yet, anyway - a money tree that bears unlimited financial fruit. The same can be said of mobility services offered by automakers.

General Motors' car-sharing service, Maven, like those more well-known companies, is still a fledgling operation experiencing growing pains. Its latest growth move involves shrinking, with the mobility brand dropping out of eight U.S. markets.

On Monday, a Wall Street Journal report called attention to GM's plan to remove the service in nearly half of its 17 markets. Among markets that can continue to expect Maven vehicles close at hand are Detroit, Los Angeles, Washington, D.C., and Toronto, though Boston, Chicago, and New York City can expect a wind-down of available services or outright desertion.

Maven launched in 2016 as a car-sharing service employing GM-owned vehicles. Like rival Zipcar, travelers or carless residents gain access to the vehicles via a phone app that tells them of their location, dropping them off after a short period of use. Hourly fees apply. Maven Gig soon cropped up, with GM offering vehicles for those who drive for ride-hailing companies or services like Uber Eats.

Looking to make money off vehicles not owned by the company, GM launched a peer-to-peer car-sharing service (Maven Peer) in Ann Arbor, Detroit, and Chicago last summer, allowing residents to rent out their own cars for extra income.

"We're shifting Maven's offerings to concentrate on markets in which we have the strongest current demand and growth potential," a GM spokesperson told the WSJ.

It seems GM wishes to have fewer Maven cars in its possession, though the exact nature of the service reduction isn't yet clear. Not all of the eight markets stand to lose all Maven services; some with retain Maven Gig (like Washington, D.C., which also loses its car-sharing and peer-to-peer service, TechCrunch reports), while others will add ride-sharing and peer-to-peer.

Everywhere, mobility is in the process of finding its feet. GM plans to offer autonomous ride-hailing services in the near future via vehicles poised to roll out of its Cruise self-driving division, though right now Cruise's expertise involves losing the company money. Maven's income-earning status remains a mystery.

In February, 19-year GM veteran Sigal Cordeiro stepped into the shoes of recently departed Maven head Julia Steyn, who led the brand since its inception.

a version of this article first appeared on TTAC