Where are you citing this information from.? Id like believe it but I always feel like the only person still complaining so to me it would seem far fetched there would be a study on it.
Let's start with looking at buisness:
1. The Microsoft Office Suite is the standard in the business world. If you had a job that used a computer on March 6th, 2006, there is an 80% chance that job used 1-3 different M$ Office programs and a 50% chance it used more than 3. I am low-balling these estimates, feel free to look up exact statistics.
2. Most of these users were non-technical people who were expressly trained at company expense in the usage of Office products for their specific tasks.
3. Most of these users needed access to advanced features of their specific office program related to their specific job.
Now let's consider a typical user:
1. Unless explicitly taught, most users do not use keyboard shortcuts.
2. Most do not make use of/know how to use built-in help functions; they were taught a process and to call IT when that process does not work.
3. Most of these people are more concerned with doing their job than mastering a program, and rely on wrote memorization of the little bits of Office they actually use. These bits remained relatively the same from Office '97 up to Office 2003, and the Ribbon didn't come until 2006.
That's 9 years of standardization thrown out the window.
Now let's look at Ribbon:
1. The UI is badly un-intuitive
2. The learning curve can best be described as a brick wall
3. And oh, yeah, early adopters did not have the option of googling "how to I access {insert basic feature now obfuscated by the Ribbon UI]" and had to rely on helpdesk tickets.
And, lastly, time on the clock cost money.
So if you look at it from the perspective of nothing other than the lost productivity as every new role out meant each user had to spend at minimum several hours re-learning the software and several months getting back up to speed on their specific business processes, that's tens of billions of dollars, easy. That is across the whole world economy, but still.
Then factor in all the time companies had to spend completely re-writing their internal training programs to accommodate the new, worse interface. Then factor in how employee training has to get
longer because the interface is so much worse.
Now factor in that because it is so bad,
just using it means many functions take precious seconds longer than they did before and factor that over hundreds of uses a day, all year long, accross the huge amount of the workforce who uses it and...
...yeah. Conservatively over the course of time since the Ribbon interface was first released, half a trillion dollars in lost productivity/lost time is a low estimate.
Of course there are many other widely used and equally awful interfaces bogging down the economy. But I am singling the ribbon out because it is the worst offender.