make install is not enough !!!

I saw that make install copies the files in x86/…
But as I think that adding the x86 directory path is really not a good
thing, it would be necessary to declare these files to the package
filesystem in order to see them in /…

And … I absolutely don’t know how to do!
Is it not the make install job?
What would be the necessity to JUST copy the files in x86/… and nothing
In fact, it seems that it would be necessary to create a package and
then install it?

Any help?