Satya Nadella took over from former CEO Steve Ballmer in 2014 and, just over a year later, wrote off $7.6 billion related to Microsoft’s acquisition of Nokia.

Nadella admitted that Microsoft’s “exit” from the mobile phone business could have been handled better.

He said that Vole’s exit of what I’ll call the mobile phone as defined then could have been made to work by reinventing the category of computing between PCs, tablets, and phones.

Microsoft finally confirmed Windows Phone was dead a few years after the Nokia phone business write-off, but it was clear six months after that decision that Windows Phone was over.

Microsoft has since launched its Android-powered Surface Duo and Surface Duo 2 handsets, but without a successor in sight and a lack of software updates, it’s unclear what the future holds for the Surface Duo.

Software King of the World and Microsoft Bill Gates said his “greatest mistake ever” was Microsoft losing to Android. Google acquired Android in 2005 for $50 million, and former CEO Eric Schmidt admitted in 2012 that Google’s initial focus was beating Microsoft’s early Windows Mobile efforts.

The shy and retiring Microsoft CEO Steve [sounds of silence] Ballmer was also slow to respond to Android and the iPhone threat, focusing the company’s efforts on Windows Mobile while famously laughing at the iPhone, calling it the “most expensive phone in the world and it doesn’t appeal to business customers because it doesn’t have a keyboard.”

To be fair he was absolutely correct, but his grave mistake was he did not realise that business people and consumers could be that dim.

Ballmer admitted in 2013 that he regretted not focusing on the phone much earlier. “I regret there was a period in the early 2000s when we were so focused on what we had to do around Vista that we couldn’t redeploy talent to the new device called the phone... That is the thing I regret the most,” he whispered.