Connectivity and Emulation
There were three reasons NeXT
computers were embraced by so many high value vertical
markets like finance, medicine and research in general:
1) While the computers were relatively expensive, the software development environment was extremely productive. In applications where there were few deployments of software then the hardware costs were nothing compared to the cost of developing the application.
2) NeXT straddled the PC and the Mainframe environments with a huge number of terminal emulators for all the proprietary main frame terminals and PC applications. As evidenced by the huge number of terminal emulators and connectivity tools listed in the menu on the left, NeXT became the rosetta stone for transferring information amongst previously incompatible systems, as evidenced by the number of terminal emulators with "screen scraping" capabilities.
"Screen scraping" is an approach where the mainframe computer has no idea it is talking to another computer. The mainframe believes it is talking to one of it's name branded terminals. Therefore no co-operation was required from the keepers of the knowledge on the mainframe for the information to be repurposed and reorganized in a more friendly environment for manipulation and rendering... the Next platform.
3) The first of the "emulators" became available on NeXTSTEP. Emulating a Mac, or a PC were available on NeXTSTEP. The company that produced SoftPC (Insignia Solutions) was later bought by Microsoft to solve some compatibly issues between the current and earlier OS's Microsoft shipped.