Day one patches for Borderlands: The Handsome Collection are pretty hefty.
Both the PlayStation 4 and Xbox One versions of Borderlands: The Handsome Collection require players to download lots of gigabytes to make the experience as smooth as possible.
The PlayStation 4 version has an 8.31GB day one patch. The Xbox One version however has a 16GB one. That's 3GB for Borderlands 2 and 13GB for Borderlands: The Pre-Sequel. Nevertheless, the developer recommends everyone download the patch before starting their playthrough.
Other than the various bug fixes in both patches, the large size is due to the inclusion of Claptastic Voyage DLC and Ultimate Vault Hunter Upgrade Pack 2, which couldn't have been added to the disc, as they've just been finished.
"For The Handsome Collection, a large day-one update will be available giving access to Claptastic Voyage and Ultimate Vault Hunter Upgrade Pack 2. This update will also address various bugs," a spokesperson said. "Although the update is large (as it's adding an entire and brand new add-on campaign), we strongly recommend that all players download it before playing The Handsome Collection."