Well according to the folks at TechCrunch, it seems like bad planning could have led to the developers running out of time to complete the updates and changes that they had planned to make, at least ahead of showing it off at iOS 8. According to one source, “Many developers left the company, no map improvements planned for iOS 8 release were finished in time. Mostly it was failure of project managers and engineering project managers, tasks were very badly planned, developers had to switch multiple times from project to project.”
Another source reaffirmed this by saying, “I would say that planning, project management and internal politics issues were a much more significant contributor to the failure to complete projects than developers leaving the group.” We should note that prior to iOS 8 being launched, there were rumors claiming that not all of iOS 8’s features would be shared at the event.
Apparently more time was being devoted to completing OS X 10.10 Yosemite on time, which is the opposite story from 2013 where more time and resources were being routed to getting iOS 7 ready on time, versus OS X 10.9 Mavericks. In any case hopefully when the iPhone 6 is launched, Apple will have more Maps details to share with us.