Why does MS request a Non-Existant PIN to set up Outlook? (Win10 Pro)

Why does MS request a PIN, when I do not have one, and do not want one.
I'm trying to set up a replacement PC, and to open a (mine) Outlook account, yet it demands my PIN.
As stated i do not have one, I do not want one, so at what point did I become an employee of Microsoft for it to insist I have one
Before I explode can someone please explain my options (bearing in mind I still do not want nor as far as I am concerned need a PIN)
Many thanks

Yes I have a password of course, and it all works fine on my old steam driven Dell; but I wanted to set up the Lenovo PC as a mirror (just in case), hence the need to copy my Outlook account. But in the past when MS have suggested a PIN I have declined, yet now asks me to enter it??? I do not have one, but there must be a workaround??

They say it's to verify who you are!

Hi Jacee
I appreciate the reply, and I also appreciate what purpose it serves, it say's it wishes to verify who I am
But i have never given this Microsoft Account a PIN. I started with a convoluted Password for it years ago, which i change on occasions and now MS seemed to have introduced something called "Windows Hello" which alludes to a PIN which has never been allocated
As suggested by Berton above I have tried the Log on the User PIN for this machine, to no avail (plus the 2nd PC I intend to switch to has quite naturally a different User log on PIN).
Somewhat exasperated, MS is a tool which seems to take up an inordinate amount of time merely in its operation
Frustrated, you bet!
Best wishes

Try this Add Picture Password to your Account in Windows 10

I can't tell if you have managed to log in or not. Assuming you are talking about logging in to an account on the replacement PC: do you not see a 'sign in options' prompt beneath the PIN field?

If you do, just select the 'key' button to enter a password. Then, once you are in, go to Settings>Accounts>Sign-in Options and click on the 'Pin' option - you should see something like this:

from where you can remove any PIN - I realise this does not explain how a PIN might have been set, but sometimes life's too short.

If your issue is with logging in to Outlook, please expand.