sentences:  This allowed easier development and replacement of games, but it also discouraged the hardware innovation necessary to stay ahead of the technology curve.Most US arcades didn't see the intended benefit of this practice since many games weren't exported to the US, and if they were, distributors generally refused to release them as simply a ROM, preferring to sell the entire ROM, console, and sometimes the cabinet as a package.In fact, several arcade systems such as Sega's NAOMI board are arcade versions of home systems.