Microsoft CEO Satya Nadella spoke to CNBC’s “Squawk Alley” on Tuesday.

“You don’t want to change everything,” Nadella told CNBC’s Jon Fortt. “You want to change the things that really matter.”

Nadella took over from Steve Ballmer as Microsoft’s CEO in February 2014.

It’s a big week for Microsoft: The company is announcing a slew of product updates at its annual conference, Microsoft Ignite, in Orlando, Fla. For instance, Microsoft is wooing new customers through software called Microsoft 365 F1, and is revamping its cloud services.

And Nadella, Microsoft’s third-ever CEO, has announced a new book about Microsoft’s future, called “Hit Refresh.”

“We as individuals are dealing with change all the time and hitting refresh,” Nadella said. “We learn from it.”

Nadella said the company is pleased with the accelerating organic growth of LinkedIn since Microsoft acquired it last year.

“That’s the start of a very healthy franchise,” Nadella said.

Nadella’s company has been active in supporting immigration into the U.S.

“The fact that the U.S. is the beacon of hope and the attraction of talent all over the world is something that we should hold as precious,” he said. “That’s where the criticism comes from, not from everything else.”

American technology reached him when he was growing up, and helped him “dream the dream,” he said.

Fortt asked Nadella about the recent expansion of the company’s Artificial Intelligence and Research group from 5,000 to 8,000 people, at a time when Alphabet, Facebook and other companies have also been investing in AI research.

“In some sense that’s the existential question for us 43 years after our formation,” Nadella said. “One thing that we realized is whatever novel concepts you came up with ultimately will stop being novel. You need to come up with the next thing.”

The company’s researchers had been exploring AI, and specifically speech recognition, for many years, Nadella said.

“It was in 1995,” he said, “when Bill said, ‘You know, this speech recognition thing is going to be important — let’s get started.'” If anything, he said, it’s about taking a long-term approach and then “seizing those opportunities when they arise.”

Fortt also asked Nadella about whether it’s risky to let Microsoft’s Cortana voice assistant talk with Amazon’s Alexa.

But there are “probably 5 to 10 million” voice-first devices, Nadella replied. “It’s just miniscule. What’s important for us is to start making it a daily habit,” he said, speaking of people using voice-activated systems.

“The strength that we have is around productivity and communications and things that professionals need,” Nadella said. “Even in a voice-first world just like how [we] put it on iOS and Android, we want to make sure our voice-first applications are available on all platforms, so that’s the fundamental construct behind it.”