signing in to a Microsoft account

lostsoul65 said:

What is the advantage of signing in to a Microsoft account when you start your windows 10 computer?

Here are a lot of the MS rationales, pulled together in one place. Honestly, if you don't need OneDrive, or any account related services, such as Store, Local is fine. You would at least need a MS account to individually sign in to Outlook, or any other MS service, on demand, each time. It;s user choice. But, here's a quick overlook, in more or less layman's terms.

Just a note for something I should have added. I see you are posting in Family Safety. You may have multiple accounts in one Windows installation, with a mix of MS accounts and local only. The "Administrator" (parent) may find it useful to sign in with a MS account, and have all others with a local, possible restricted account.

If you have a Microsoft account, you can switch to a local and vice versa. You're not locked in.

Why Should I Bother with a Microsoft Account for Windows 10? - dummies

In addition:

Microsoft Accounts (Windows 10) | Microsoft Docs

I'm sure it is posted in the articles provided but a Microsoft Account allows you to reset your password online.

If you have a local account, and it is the only admin account, and you forget password you need to do some special steps to get access to device again.