Ha! From the mid 1980's until the mid 1990's, both Nintendo and Sega ruled the videogame industry with their Nes, GmeBoy, SNES, N64, Sega Master System and Sega Genesis and then the wheels fell off. Nintendo wanted to keep their lucrative cart based business model that had served them well during the 8-bit and 16-bit era and then they kept to that model with the N64 right around the time CD based consoles started to appear/

It's been downhill for Nintendo ever since and Sega bowed out of the console business altogether. Nintendo's stellar franchises of Mario, Zelda etc have stood the test of time but more and more adults were becoming gamers and as folks who grew up on Nintendo reached early adulthood, they wanted games that reflected that and they found that with the Playstation.

Nintendo has for the most part completely ignored adult gamers. They still design and market their games for kids.