How do you define your legacy when the numbers stack up against you? Ginni Rometty, former chief executive and chair of IBM, is confronted by this conundrum every day.

Rometty and some who worked closely with her say she was pivotal in transforming the century-old US company: reinventing half its portfolio of businesses; building its cloud computing division; and establishing its leadership in artificial intelligence and quantum computing.

But critics counter that she was too slow at taking decisive action to move an old-world tech company into AI, the cloud, and data analytics. IBM’s business customers were moving from in-house products managed by the company to outsourced services in the cloud, where rivals Amazon Web Services, Microsoft and Google parent Alphabet were ahead.