As the storage size of digital media has increased, so too has the size of the video games that are played. Game worlds used to be quite tiny, and the length of games came from other areas of difficulty meant to make it hard to explore those worlds. Enemies were difficult and frequent; statistical balance was brutal. It would take players hours to get the right equipment, enough money, and high enough stats to be able to properly progress. Games have been expanded in many ways for decades.
The idea of playing through a game twice or more is quite old by now, with the earliest examples coming from some mid-80s hits and classics such as Ghosts 'n Goblins, The Legend of Zelda, and Digital Devil Story: Megami Tensei. The rewards for this choice are varied, the true ending for Ghosts 'n Goblins, or an extra challenge in Zelda and Megami Tensei. It was only later when this idea was not only popularized, but received a name that has stuck with gamers for over two decades and counting now. Chrono Trigger rewarded players for multiple trips through its world by offering a variety of different endings that could be achieved by beating the final boss in any number of different ways and almost anywhere during the story.
