Bytecode is much closer to source code than machine code (there's a cool discussion about this in https://channel9.msdn.com/Shows/Going+Deep/Expert-to-Expert-Er

Bytecode is much closer to source code than machine code (there's a cool discussion about this in https://channel9.msdn.com/Shows/Going+Deep/Expert-to-Expert-Erik-Meijer-and-Lars-Bak-Inside-V8-A-Javascript-Virtual-Machine https://channel9.msdn.com/Shows/Going+Deep/Expert-to-Expert-...) and source code is generally smaller than machine code.