He also rejected the notion that because users adapted to the shift 17 year ago from DOS to Windows 95 that they will gladly do the same this time with Windows 8.
"The difference is that then they took something really bad, DOS, and added something, Windows, on top of it that was much easier to use," Nielsen said. "This time they're taking the standard GUI [graphical user interface] that has a lot of usability and discoverability, and making a U-turn by hiding features."
The result is a user adrift from the hard-won experience gained through years of time spent working with Windows.
"With Windows 8, you don't feel in control," said Nielsen. "One of the biggest goals of user interface design is to give people the feeling of mastery or control. This is a big, big change. Users have become familiar with the idea that the 'mouse is me,' but Windows 8 largely discards that. People feel a loss of control, and feel insecure in relation to the machine.
"That's the failure, and the missed strategic decision," Nielsen said.
Microsoft has, of course, trumpeted the massive UI changes as a step in the correct direction, not a wrong turn, calling Windows 8 "fast and fluid," labeling it a "no-compromise" solution, and dismissing criticism that Windows 8 is difficult to use.
In an interview prior to the Oct. 26 launch of Windows 8 with the IDG News Service -- like Computerworld, part of IDG -- Tami Reller, the Windows division's CFO, said Microsoft had done hundreds of usability tests during development, both in labs and in real-world settings.
Reller said Microsoft's results were directly opposite Nielsen's conclusions. "Within 24 hours [Windows 8] users were using 80% of the core capabilities of the operating system," Reller told IDG News reporter Joab Jackson. "And they just get faster every day."
What the company hasn't clearly explained, however, is why it did what it did, rather than develop a new OS for tablets that didn't also intrude into PC turf.
Nielsen has some ideas. "There's the marketing angle, of course, the 'Let's make one Windows,' but there's also the fact that it seems to have been engineering-driven," said Nielsen. "And all the engineers were probably thinking, 'It's not so bad, people can figure this out,' because they're brainy people and can manage to keep more things in short-term memory than most. And then there's the Apple envy, wanting to make something cooler than Apple. But they shouldn't have done that at the price of sacrificing usability."
Nielsen was confident that Microsoft could correct the mistakes of Windows 8, in part because of last week's executive reshuffling that sent former Windows division chief Steven Sinofsky packing and promoted one of his lieutenants, Julie Larson-Green, a user interface expert, to head all Windows hardware and software development.
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