N64 was a failed console in terms of game library, but it was pretty decent hardware wise. It's the least eye-sore for 3d games in that era IMHO, .
But in terms of 2D, Saturn destroys both N64 and PSX combined. Late '90 was full of mindless hate against 2D and Saturn was 2D powerhouse.
Oh, and Jaguar too.
Too much of a powerhouse. Ultimately Sony played the price war and made it very difficulty for Sega financially because of the raw cost of producing multi-processor hardware in the 90s. Plus like I said, not too many developers were ready to really exploit the machine, the idea of making multithreaded games only really took full traction in the mainstream by the time of the Xbox 360, a decade after the release of the Saturn.
From a game dev of the time :
"One very fast central processor would be preferable. I don't think all programmers have the ability to program two CPUs—most can only get about one-and-a-half times the speed you can get from one SH-2. I think that only 1 in 100 programmers are good enough to get this kind of speed [nearly double] out of the Saturn."
—Yu Suzuki reflecting upon Saturn Virtua Fighter development
Later on, Sony got hit in the same way and made the same sort of mistakes (but unlike Sega, survived) with the PS3. The PS3 can't be considered a failed console, but it lost a lot of marketshare for Sony, who used to be almost dominant in the console space (apart from Nintendo's consistent market segment) since the PSX. Released with a funky architecture and a high price point leaving MS to dominate the price war and the ease of development, shooting the Xbox from irrelevance (the first xbox was a failure in sales) to half dominance. It's hard to imagine right now, but without that mistake, the playstation would still probably be the only major platform to exist - og xbox sold 24m units, versus 158m for the ps2. Losing a quasi-monopoly all in the name of the god Hubris.