Honestly not sure why this is downvoted. I run a multi-user setup and switching between users is a giant pain. Here is one scenario that I find really weird, at the very least since High Sierra.

Assume user MAIN and user WORK:

1) Open Macbook

2) Login prompt for MAIN shows, "Switch User" button below

3) Click "Switch User", now prompt with logins for MAIN and WORK shows

4) Click and successfully login to WORK, the desktop for WORK now shows

--- Getting weird now

5) Get flashing image of desktop of user MAIN (?)

6) Get login prompt for user MAIN (??)

7) Click cancel, bounce back to login screen with MAIN and WORK (???)

8) Login to WORK again, good to go from here.

Switching between users on macOS is not just weird sometimes but at least it feels downright insecure when I am able to see flashing images of MAIN when I am logged into WORK.