UNIX/Operating system question

Why can you, a non-root user with limited permissions, not change the owner of a program to be the root user? Because if the SUID bit is set on the program, we can write programs that will run as root, and thus can do anything on the system Because we will lose access to the file, as we cannot take it back from root Because if the SGID bit is set, the UNIX group were in will lose access to the program without warning, which is against the meaning and intention of the SGID bit