backup – Why are subfolders "larger" than the parent folder?

I'm trying to move an incremental backup produced with something like Rsync. Although I understand the basics of hard links, this does not seem to explain the following information about the backup directory tree.

It may be interesting to know that the source directory tree is about 400 GB and that the full incremental backup has been moved to occupy 2.4 GB of hard disk space.

For the question to remain simple, how (under Win10) a parent folder can display a total content of 497 GB, while a single subfolder displays content greater than 900 GB?

washing machine 16 WIN 10
-h –max-depth command = 2 folder properties

media 8 TB 4000 GB 497 GB

media 8 To 10/31/2017 284 GB 106 GB
media 8 To 27/11/2017 283 GB 106 GB
media 8To 27/12/2017 285 GB 109 GB
media 8 TB 27/01/2018 286 GB 109 GB
media 8 To 27/02/2018 219 GB 41 GB
media 8 TB 27/03/2018 220 GB 42 GB
media 8TB 27/04/2018 221 GB 18 GB
media 8 TB 27/05/2018 220 GB 15 GB
media 8 To 27/06/2018 221 GB 15 GB
media 8 To 7/27/2018 221 GB 15 GB
media 8 To 27/08/2018 221 GB 15 GB
media 8TB 10/2/2018 238GB 2GB
media 8 To 10/27/2018 238 GB 111 GB
media 8TB 12/6/2018 240GB 904GB
media 8 TB 27/12/2018 240 GB 904 GB
media 8 TB 27/02/2019 404 GB 39 GB