Windows folders "working on it"

[chronuss]

I recently had a problem where I had to change ownership of a bunch of files/folders with a decent amount of anime episodes in each folder on one of my computers specific drives because of a weird user account that was a SID having ownership. Now when I open the folders it takes a bit longer for the page to populate with the files inside. It says "Working on it" when I open any of the folders, but loads instantly once it has been opened once.  I know this sounds stupid, but isn't it supposed to pre-find all the files when the computer starts? I thought all the folders open instantly basically once the PC loaded after being turned on. Is it supposed to have a delay each time you open a folder the first time after a restart?