[Q] Device Memory - Internal Storage Doesn't Add Up topic

I noticed that if I add up the size of the files in my device memory, it comes out to be over 16GBs, but I still have more than 1GB of available space. I have attached screenshots of this. Does anyone know how this could be? When i install a large app, the app space goes up but the available space does not go down. I'm on MK2, rooted and running Hyperdrive RLS 14.

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