Why the size of update is same of the size game

I cant send a screenshot right how

But the update size is the same size as the actual game size

The game install sizes are also listed on the Xbox One game store, on the console and here on Xbox.com. The download sizes are exactly the same as the disc install sizes.

As to the install size to actual game size ratio, that one is easy to explain. The size of a game install isn't necessarily bigger because the game is 'bigger'. The size really depends on the game assets, things such as textures, high definition audio and
HD video sequences. This explains why AC4 is 7.63GB on Xbox 360, and 20.81GB on Xbox One.

Hi, that's usually what happens when you download an update. Most of the time updates install over the files that need updating. It's not like the xbox 360 where an update is installed and adds to the file size. With Xbox One games, updates are installed
over files that are needed to be updated. hence why the file size has not changed.

The great thing about updates on the XBox One is that some files are overwritten with the updated version, meaning it doesn't chew up as much storage space. Great when you consider just how big some of these games are these days!

I see, thanks for your time, I was getting worried