In addition to what others said, due to the architecture it was notoriously hard to develop for. The Playstation dev kits were a dream to work with in comparison. Sega of Japan hedged their bets on 2D remaining king due to the Japanese market preferring arcade ports and slowness to accept change, and slapped on some 3D capabilities almost as an afterthought. Meanwhile Sega of America assumed the US market would scoff at spending 500 on a console when the 32X had just released and was very similar (and also selling poorly).

Sony took risks by pushing 3D hard, were aggressive with pricing, did a ton of marketing, and completely ate Sega’s lunch. Despite the Saturn being arguably more powerful and better made than the PS1, it wasn’t enough to right the ship. And it continued on this downward spiral due to the negative impressions that Sega was dying with the Dreamcast where they again flubbed the launch timing while people were enamored with the N64 and the PS1 had a massive library.

There were lots of other shenanigans involved, I’m skimming the surface here. Regardless, both consoles have some bangers and I recommend trying some out if you ever have the chance. The hardware is also very cool if you can find them cheap but might need refurbed at this age.