Why was assembly code created?

To program computers without having to memorize all of the numeric opcodes and other values used in machine code.

However assembly code is exactly as machine specific and tedious to program with as is machine code. The program has to be completely rewritten from scratch in another assembly language to port the program to a different computer.

High Level Languages were created to allow programming to be done in terms that people more easily understand and to simplify porting programs to different computers.