Every company desperately wants you to create an account with them, and usually the main reason is that the marketing team told the executives that they can collect "user data" or "analytics" and make a fortune off of it. Of course it turns out they can't actually do anything useful with it except build a profile on you for marketing purposes, which they either use directly to serve you targeted ads (in Microsoft's case, through the OS itself), or sell it to a company that does.
That's the whole purpose of the "create an account to use our service that suspiciously doesn't need an account at all!" thing. To show you advertisements.
So they can tell their advertisers that they served their ads to people who have 50% more potential to be customers, or something.
And then those advertisers can keep on making their annoying ads that make their best potential customers actively hate them, but test well because most people are stupid.
It's a vicious cycle of corporate stupidity. No one actually benefits from this stuff. No one actually makes more money. But a lot of people *feel* like they're doing something useful.
Our society has become so affluent that mediocre products, engineering, and development can bring in enough money to subsidize management, executives, and marketing that actively suppress demand for the company's products.
It's remarkable, really.
World's foremost 486 enjoyer.