From The Man Who Is Transforming Microsoft:

[Satya Nadella] moves to another group of kids and then shifts his attention to a teenage student who is blind. The young woman has been working on building accessibility features using Cortana, Microsoft’s speech-activated digital assistant. She smiles and recites the menu options: “Hey Cortana. My essentials.” Despite his transatlantic jet lag Nadella is transfixed. “That’s awesome,” he says. “It’s fantastic to see you pushing the boundaries of what can be done.” He thanks her and turns toward the next group.

“I have a particular passion around accessibility, and this is something I spend quite a bit of cycles on,” Nadella tells me later. He has two daughters and a son; the son has special needs. “What she was showing me is essentially how she’s building out as a developer the tools that she can use in her everyday life to be productive. One thing is certain in life: All of us will need accessibility tools at some point.”

https://blog.mozilla.org/nfroyd/2016/11/29/accessibility-tools-for-everyone/