Bloomberg:

On calls in mid-April, an Apple Arcade creative producer told some developers that their upcoming games didn’t have the level of “engagement” Apple is seeking, the people said. Apple is increasingly interested in titles that will keep users hooked, so subscribers stay beyond the free trial of the service, according to the people.

And:

On the calls with developers in April, the Apple Arcade representative cited a specific example of the type of game the company wants: Grindstone, an engaging puzzle-action game by Capybara Games that has many levels.

And, from Apple:

“Apple Arcade has redefined what a gaming service can be, putting unlimited play at the fingertips of subscribers and their families across all their Apple devices,” Apple said in a statement. “We are proud to have launched the first-ever mobile game subscription service that now features more than 120 games, many of which are award-winning and widely celebrated for their artistry and gameplay. The vision has always been to grow and evolve the Apple Arcade catalog, and we can’t wait for our users to try the games developers are working on now.”

This seems a sound business strategy. For Apple Arcade to work, it needs the revenue from users who pay to stay beyond their free trial. And games that pull users in are going to be the winners here, both for their studios and for Apple.