Why is too much space reserved when updating a program / game?

I have a problem again and need your help. The point is, if I want to update a program or game, in this case Fortnite, I'm reserving too much memory space than the program / game needs. For example, the update only needs 250MB and 40GB reserved. Can someone help me there?

P.s: I have Fortnite on a 220GB SSD (where my operating system is on it) on it.

For further questions just ask.

It is quite normal for the update process to additionally temporarily reserve the total size of the application to be updated.

Although the update has only 250 MB, but it must also be "integrated". Since this probably does not happen in-place, it takes up all the space.