Every new sequel is now expected to be bigger than its predecessor and have better technology. This, in turn, is also reflected in brand new releases in the so-called big game category, as expectations are always high. Previously it was said that major productions needed up to three years of development, but today the development time has grown considerably and is four to six years.
In an interview with Axios, Xbox Game Studios boss Matt Booty says it's no wonder that titles like Perfect Dark or Fable are taking so long because they were announced very early in the process, and there's still a long way to go:
"I think that the industry and the fans were a little behind the curve on sort of a reset to understand that games aren't two or three years anymore, they're four, and five, and six years. The level of fidelity that we're able to deliver just goes up. Games continue to get more ambitious as an art form."
This is also why Microsoft has bought so many studios, as they hope to deliver about four new games every year going forward.