How has Mario remained popular, when other Cartoon Videogame characters have failed or declined in popularity?

[Clyde32]

spurgeonryan said:

AZWification said:

Mario has remained popular, because his games are always at least decent! Spyro suffered from the sub-par PS2 games and Skylanders, Crash suffered from the PS2 games  and Sonic suffered from crappy games like Sonic 3D Blast and Sonic 06!

Yes, but what makes Nintendo so different? Why or are other developers so inept that they cannot make their games properly? Not enough funds? What?

Nintendo finishes their games.