The first three Halo titles were all about Master Chief John-117 as the hero, but more recent titles like Halo 3: ODST and Halo: Reach went away from this focus. To Microsoft Game Studio president Phil Spencer, Halo is about Master Chief’s adventure.

What does that mean Playing Master Chief, said Spencer. We kind of lost our way a little bit, I ll say.  And that s why I wanted to make sure that at the unveiling of Halo 4, you knew you were playing Master Chief, that John was back. Because Master Chief is the John Wayne character of that universe, and that s who you want to play.

If you were a Halo fan for Halo 1, 2 and 3, Reach made sense to you, but fundamentally there are a ton of players on our box right now that didn t start with Halo 1, he added. I loved Reach as a game as a fan of the fiction, I totally love the story in Reach, Reach is one of the best stories in the Halo universe. But it made more sense to you if you were a Halo fan. If you were new to Xbox 360, 360 s where you started playing on Xbox, you understood what Halo 3 was. ODST and Reach, maybe you weren t as centered.

Source: OXM