Message Mixer steps 9 - 10 Explaination for how the solution to those exercises work

Hey Codecademy,

I have a question about functionality within steps 9 & 10 in the lesson “Message Mixer” found here:
Message Mixer Exercise

I had to look at the hint’s for these steps because I was so confused.
Here is my question:
How does returning this within the function:

const decodeMessage = (str) => {
  // Use the encryptor functions here.
  caesarCipher(symbolCipher(reverseCipher(str)), -6);
}

Am I creating a path to find? How does this create functionality? Sorry if this is a vague question, or if I’m not making sense. I just don’t understand how the solution was found, and how the soloution works.

Below is a larger portion of my code.
Thanks so much for the help.

// Import the encryptors functions here.
const {caesarCipher, symbolCipher, reverseCipher } = require('./encryptors.js');

const encodeMessage = (str) => {
  // Use the encryptor functions here.
  return reverseCipher(symbolCipher(caesarCipher(str,6)));
  
}

const decodeMessage = (str) => {
  // Use the encryptor functions here.
  caesarCipher(symbolCipher(reverseCipher(str)), -6);
}

did you make a line break after the return keyword? Javascript sees that as two different statements and leaves the function after the return then.