Why was I sent to the sign-in page? Did my session end?
The dashboard is only visible while you're logged in; when your session ends, the sign-in page opens, and you return to the dashboard when you log in again.
Dashboard pages are only visible while you're logged in. If your session has ended, the sign-in page opens instead of the page you wanted. When you log in again, the dashboard's main page opens; use the menu to go back to the previous page.
If you signed out in another tab of the same browser, the tabs that are still open switch to the sign-in page; if you logged in with a different account, they switch to that account's dashboard. In both cases, the previous account's screen isn't shown.
If you see “We couldn't verify your session” on the screen, the server couldn't be reached at that moment; this doesn't count as signing out. Check your connection and press the “Try again” button, or use the “Go to the sign-in page” link.
To end your session yourself, use the “Sign out” button at the bottom of the left menu. If you open the sign-in page while you're logged in, you're taken straight to the dashboard.