Exit code at the end of a bash script

I am confused about the meaning of the exit code in the end of a bash script: I know that exit code 0 means that it finished successfully, and that there are many more exit codes numbers (127 if I'm not mistaken?) My question is about when seeing exit code 0 at the end of a script, does it force the exit code as 0 even if the script failed or does it have another meaning?