Miranda's cost was a big problem, but not the only one. The other core issue that lead to the creation of Haskell was Miranda's license that essentially prohibited using it as a tool for programming language research. For good reason, Turner (Miranda's creator) wanted to avoid the fragmentation of Miranda into different dialects. From [1]:
> [T]he easiest way to move forward was to begin with an existing language, and evolve it in whatever direction suited us. Of all the lazy languages under development, David Turner’s Miranda was by far the most mature. It was pure, well designed, fulfilled many of our goals, had a robust implementation as a product of Turner’s company, Research Software Ltd, and was running at 120 sites. Turner was not present at the meeting, so we concluded that the first action item of the committee would be to ask Turner if he would allow us to adopt Miranda as the starting point for our new language. After a brief and cordial interchange, Turner declined. His goals were different from ours. We wanted a language that could be used, among other purposes, for research into language features; in particular, we sought the freedom for anyone to extend or modify the language, and to build and distribute an implementation. Turner, by contrast, was strongly committed to maintaining a single language standard, with complete portability of programs within the Miranda community. He did not want there to be multiple dialects of Miranda in circulation and asked that we make our new language sufficiently distinct from Miranda that the two would not be confused. Turner also declined an invitation to join the new design committee [...] Haskell owes a considerable debt to Miranda, both for general inspiration and specific language elements that we freely adopted where they fitted into our emerging design.
[1] P. Hudak, J. Hughes, S. Peyton Jones, P. Wadler, A History of Haskell: Being Lazy With Class.
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