sentences:  According to Sony, when they removed backwards compatibility from the PS3 they had already been at a point where they were three years into its lifecycle; by that time the vast majority of consumers that were purchasing the PS3 cite PS3 games as a primary reason, meaning that the PS2 compatibility was no longer necessary.Nevertheless, PS2 Classics which are playable on the PS3 have officially been introduced to the PlayStation Network for purchase afterwards, although they are only a selection of PS2 games republished in digital format and unlike PS3 games they lack of Trophy support.Later when the PlayStation 4 console was released, it was not backward compatible with either PlayStation 3 or PlayStation 2 games, although limited PS2 backward compatibility was later introduced, and PS4 owners might play a selected group of PS3 games by streaming them over the Internet using the PlayStation Now cloud-based gaming service.