At this point, it's fair to say that the Windows 10 October 2018 Update is the worst rollout of a Windows 10 version to date. Originally released on October 2, it was pulled four days later due to some users' files being deleted upon upgrading. After that, things only got worse.
It was discovered that extracting ZIP files doesn't produce a dialog box for whether you want to overwrite files, so the operation fails without telling users. Moreover, if you tried to cut and paste from a ZIP folder, the operation would fail and those files would actually be deleted.
The Windows 10 October 2018 Update is currently blocked from being installed on some Intel PCs due to driver issues, and also on PCs that have Apple's iCloud installed. Microsoft has also outlined issues with network drives, and certain older AMD GPUs.
But wait, because there's more. Now, there's a known issue that prevents the user from seeing the Seek Bar in Windows Media Player. The known issue was recently added to the company's documentation for the latest cumulative update for Windows 10 version 1809, which was released on November 13.
The update was KB4467708, and it was a day one update for the Windows 10 October 2018 Update. Well, it was the second day one for the update, as it was re-released on the same day. The only known issue at the time was that users might not be able to set default apps.
Presumably, things can only get better from here. More cumulative updates will arrive, likely more than once a month, and all of these issues will get fixed over time.