Q I often used to access the Library folder in my Home folder. Why has Apple hidden it from the Finder?
A Prior to OS X Lion, that Library folder was shown in regular Finder windows, and included in the Finder’s Go menu.
From Lion onwards, in a bid to improve its security, Apple has hidden it from normal view. An important folder with quite sensitive contents – in some ways as critical as the top-level Library folder, changes to which require authentication – it did not make sense to restrict access by permissions. After all, the ~/Library folder is in your Home Folder.
Making it invisible is a compromise which should make you less likely to access the folder unnecessarily, or accidentally. If you find this really irksome, third-party utilities can make it permanently visible. However it is still straightforward to access when you need: hold the Option key down when selecting the Finder’s Go menu and it is enabled in the list of destinations, or you can select your Home Folder and type Library into the Finder’s Go to Folder… dialog.
Updated from the original, which was first published in MacUser volume 28 issue 16, 2012.