Why does StorageManagement keep quitting whenever I want to look at storage? So recently I have been noticing that I have lost about 12 GB of storage randomly. Of course, I loaded up Daisy Disk and try to find the issue (with no luck unfortunately), so I decided to see what I could do with the Apple Storage Managment features. 

So I headed over to Apple -> About This Mac -> Storage to look at the summary. I see the following screen:



A few seconds later, this pops up:



The Storage panel keeps on "calculating", and I cannot use the default functions provided in Manage Storage. Does anyone know how to fix this? I am on a MacBook Pro Mid-2014 on macOS Sierra 10.12.5
Reindex the Spotlight Index by following these steps:


Choose Apple menu () > System Preferences, then click Spotlight.
Click the Privacy tab.
Drag the folder or disk that you want to index
again to the list of locations that Spotlight is prevented from
searching. Or click the Add (+) button and select the folder or disk
to add. 


To add an item to the Privacy tab, you must have ownership permissions for that item. To learn about permissions, choose Help from the Finder menu bar, then search for “permissions.”


From the same list of locations, select the folder or disk that you just
added. Then click the Remove (–) button to remove it from the list.
Quit System Preferences. Spotlight will reindex the contents of the
folder or disk.


From: https://support.apple.com/en-us/HT201716