Rift developers Trion Worlds first released their beloved MMO with a subscription-based payment model. It seemed like the right way to go at the time, especially when youre trying to match the success of something as massive as WoW. But some years later, they changed over to free-to-play, and like with any MMO thats done that in the past, it didnt work out as well as they had hoped.
Source: N4G PC Rift Prime Has It Worked?