We've been wondering why it's taken Square Enix so long to churn out another installment in the core Final Fantasy franchise, seeing as how the last game came out approximately forever ago. The answer recently came in the latest Dutch issue of Official PlayStation Magazine, which contains a revealing interview with Squeenix's Yoshinori Kitase. According to a fan translation of the interview, Kitase said "Final Fantasy XIII was originally meant to be a PS2 title, but we had to switch systems due to the arrival of the PS3. That cost us about one and a half years and was constantly a case of trial and error."
Considering it took Square Enix roughly "one and a half years" to develop and release Final Fantasy IX, that's a pretty substantial amount of time lost. Hopefully the developer will have an easier time when working on the next current-gen Fantasy.