To show the size of a folder, Windows Explorer would have to read ever file within every sub-folder before it could return a result.
The most likely reason it does not display folder sizes is that it would slow down browsing of the file system significantly. Size column in Windows File explorer shows sizes for files, however it doesn’t show folder sizes for folders. Also, if the hard drive reaches its storage limit, we will be facing performance, access and speed problems of reading and writing the information stored on the disk. We can delete some extra files from that folder to make some space free for other programs or files.
Large folder size is one of the most common reasons behind our computer systems slowing down or lagging. The management of the space on the hard disk is a fundamental task.