It's probably similar to getting the game done in Frostbite. Which BTW I'm on on the verge of whether that's gonna be good or bad for NBA Live.
While we, players, like Frostbite for how well it typically runs and looks, devs apparently dread working with it. There's only so much manpower the Frostbite support team can produce to help other teams with implementation of the engine.
Frostbite was apparently partially reason of why Mass Effect: Andromeda and Anthem crashed like they did - main reason was managerial failure, but Frostbite caused headaches too. (
interesting read here)
Basically the BioWare devs had to for example make their own manual save and load features for the Dragon Age: Inquisition.
Now think about how many features they'd have to make for an NBA game.
And that's where it ties back into the sales. FIFA as the main cash cow of EA gets preferential treatment. NBA is not anywhere close to FIFA to get the same level of support internally.