When Fast Startup is enabled, your computer doesn’t perform a regular start up or shut down. Its like a hybrid sleep mode and over time things can get corrupted as the kernel is not getting fully initialized from scratch. Also your video driver is not getting fully reset at boot up. Disabling fast boot helped reduce the number of stutters on my PC. See article below
https://answers.microsoft.com/en-us/windows/forum/all/what-is-fast-startup/8c08b3cf-7f31-4857-8e77-09351906f3a5