Trying to find a technological fault is what people did at the time. There were long threads on Usenet trying to ascribe things anecdotally to hypotheses that even then did not hold water.

It's sad to see looking for technological reasons happening here in the replies to your question, because that means that subsequent history has been forgotten. The technology turned out later in the decade never to have been the deciding issue, when things like the "Halloween documents" came to light. It was business agreements and marketing that sunk such products (albeit that one can argue that one can find traces of NeXT around even to this day), not technology. There were exclusionary pre-loading agreements with Microsoft, infighting inside IBM between two divisions, some utterly self-destructive litigiousness by some companies, and a whole bunch of Apple politics.