I would guess that one reason so many legacy big tech companies failed to compete against AWS is that they had a critical mass of sellers who were not equipped to sell cloud. Combine that with existing relationships with CIO/IT folks who were incentivized to maintain the status quo makes it very hard to actually do things differently. I believe the key thing AWS changed was that the sellers were not gatekeepers to purchasing. AWS sellers had to figure out how to add value beyond just doing demos and negotiating pricing and contracts. I doubt IBM was willing to change it's sales process or who it targeted for building relationships within the customers organizations.