But if they had nurtured their talent so that they didn't have to re-train testers, programmers and designers every 12 months, they might have finished it in three-quarters of the time.
Plus nurturing the talent means they can easily roll into the next project with little or no downtime, which makes that project cheaper to complete.
So you can argue that both methods - being cruel to the employees and being very nurturing - deliver good games but take a lot of time.