Board Thread:Sly Cooper: Thieves in Time discussion/@comment-3244796-20130324045045/@comment-1845428-20140702000428

Reusing any of the programming from the old games would have been near impossible. It is sorely outdated, and wouldn't run on PS3 without a ton of extra work, and therefore would have cost much more than just starting from scratch. So if they somehow did use the programming from the PS2 games, the cost would have been upwards of $25,000,000 to $30,000,000, though most likely more.

Think of it as if you were making a jigsaw puzzle. It would take a lot longer to take pieces from another puzzle and try to make them fit perfectly than if you just started with a single sheet of cardboard and cut it all yourself.

-Teenbat