What causes the QuickBooks login loop?

https://quickbookhelpdesk.com/blog/quickbooks-infinite-login-loop-issue/

Common causes include outdated browsers, damaged cache files, corrupted cookies, unstable internet connections, outdated QuickBooks versions, browser extensions, and temporary authentication problems. The QuickBooks infinite login loop can prevent access to your accounting information, but the issue is usually related to browser data, outdated software, internet connectivity, or temporary authentication problems rather than serious software failure.