Each copy of the source program must be translated into an executable program that is correct for each machine:
Ideally, only one program needs to be written in the high level language. That source file can then be translated into several executable files, each containing the correct machine instructions for its intended processor. This is how the same game can be made for desktop computers and game machines.
The idea of using one source file for executable programs that run on different processors is called software portability. You would like to write a program just once (in a high level language) and then to run it on any computer system by translating it into that system's machine language.
Usually, unfortunately, things do not work out that nicely. There are enough little problems so that it takes a substantial amount of human effort to get a source program running on a several different systems. Sometimes it is months before a game program that has been released for PCs is released for game consoles.
One of the big advantages of Java is that it is automatically portable between computer systems that have Java support. No human effort is involved at all.
Say that a corporation pays programmers $50 an hour to write application programs that will run on both Apple and Windows computers. Will the corporation want programmers to program in Java or in some other high level language?