The "NeXT Cube" was essentially the same thing as the "NeXT Computer" with an updated CPU. Basically, they renamed it after they released the "NeXTstation"[0] to avoid confusion. Otherwise, they'd have had two NeXT "Computers." Heh.
Though fine in 1988, NeXT's own hardware was rather under-powered for the early 90's. Their main competitor, Sun, was transitioning to their own RISC architecture (SPARC) after originally being on 68K. DEC was coming out with the Alpha. HP had moved to PA RISC. Though I digress, it's too bad NeXT never ran on the Alpha! That would've been a killer 90's setup.
Though fine in 1988, NeXT's own hardware was rather under-powered for the early 90's. Their main competitor, Sun, was transitioning to their own RISC architecture (SPARC) after originally being on 68K. DEC was coming out with the Alpha. HP had moved to PA RISC. Though I digress, it's too bad NeXT never ran on the Alpha! That would've been a killer 90's setup.
[0]: https://en.wikipedia.org/wiki/NeXTstation