Why does my Venu 3 only have a little more than 4 GB of free space left?

My Venu 3 seems to have only 4.18 GB of space available, out of a total of 7.08 GB.

Garmin Venu 3's internal storage says only 4.18 GB available out of 7.08 GB

I checked to see if there is anything that is taking up a lot of space on the device, but nothing seems to be taking up much space. When I check how much space all the folders on the device takes, the "Audiobooks", "Music" and "Podcasts" folders take up no space as I did not put anything in them. The "GARMIN" folder only takes up 16.2 MB of space as shown in this screenshot:

So, where is the nearly 3 GB of space gone? Is it for the Venu 3's firmware? Surely it cannot take up that much space!