There are always good games on a console, but the successful consoles have that game(s) that sells consoles, and ends up putting a stamp on the console saying "go buy this" and drive console sales. Those are the killer apps.
Killer apps are for sure a big reason why consoles are successful. And if a console has no killer app to be found anywhere in the library, it can pretty much say goodbye. The TurboGrafx 16 is a console that I think is pretty good, but with all honesty it didn't have a true killer app. Even though it had good games like Blazing Lazers, Super Star Soldier, and Bonk's Adventure. This also applies to the Sega Saturn and the Sega Master System which had good games, but not a true killer app.
If you don't believe me that killer apps are important, I'll prove it to you. Most gamers agree that the first ever killer app was the Space Invaders arcade port for the Atari 2600. In fact Space Invaders was the first ever video game to sell one million copies. For the record, killer apps should be critically acclaimed by most people; so Pac-Man on 2600 doesn't really count even though it sold seven million copies.
Every Super Mario Bros and Legend of Zelda game could easily be a killer app for all Nintendo consoles. Super Mario Bros to the NES, Super Mario World to the SNES, Ocarina of Time to the Nintendo 64, and so on. Other examples are the Donkey Kong arcade port of the Colecovision, Tetris to the Game Boy, Sonic the Hedgehog to the Genesis, Final Fantasy VII to the Playstation, Soulcalibur to the Dreamcast, the Grand Theft Auto series for the PS2, Halo for the Xbox and Xbox 360, and the Uncharted series for the PS3. After all that, why is the Wii U not selling well? You tell me.
If you don't believe me that killer apps are important, I'll prove it to you. Most gamers agree that the first ever killer app was the Space Invaders arcade port for the Atari 2600. In fact Space Invaders was the first ever video game to sell one million copies. For the record, killer apps should be critically acclaimed by most people; so Pac-Man on 2600 doesn't really count even though it sold seven million copies.
Every Super Mario Bros and Legend of Zelda game could easily be a killer app for all Nintendo consoles. Super Mario Bros to the NES, Super Mario World to the SNES, Ocarina of Time to the Nintendo 64, and so on. Other examples are the Donkey Kong arcade port of the Colecovision, Tetris to the Game Boy, Sonic the Hedgehog to the Genesis, Final Fantasy VII to the Playstation, Soulcalibur to the Dreamcast, the Grand Theft Auto series for the PS2, Halo for the Xbox and Xbox 360, and the Uncharted series for the PS3. After all that, why is the Wii U not selling well? You tell me.