I read this recently on the development process and I think it raises several salient, crucial points over the history:
1 - Poorly coordinated effort originally between separate, distant departments for high inefficiency,
2 - Restrictions from the engine, which initially limited those to employ, and requiring extensive modification which should've maybe had them creating their own engine at the start,
3 - Decision to develop all elements collectively of the complex project without either a concrete framework established (definite compatibility upon integration) or a progressive build of each element, focused, which adds onto (confirmed) successful versions (easily contrasted).
Many of these issues, I believe, have been rectified *since*, I hope, from improvement to their management and project planning.