New Delhi, July 14 -- "We did not adapt and move quickly enough."

IBM reported second-quarter revenue of $17.2 billion, up one percent from a year earlier but below analyst estimates. The headline number masked a significant divergence across the company's businesses. Infrastructure revenue fell seven percent, pulled down by IBM's Z-series mainframe and Transaction Processing software lines, as clients redirected capital spending toward servers and storage purpose-built for artificial intelligence workloads rather than IBM's proprietary mainframe stack. Software revenue rose five percent. Consulting grew one percent at constant currency. Red Hat, the open-source software business IBM acquired in 2019, accelerated to 11 percent sequential...