"...they looked over my latest script...said that I should have an exit statement at the end, before all the subs. I do not see the need for exit..."

I've been told to do this a while ago.

If "they" insist give them their fu****g main AKA block and this exit, it doesn't hurt:

#!/usr/bin/env perl

use strict;
use warnings;
use feature qw(say);

MAIN: {
    say karl();
    exit 0;
}

sub karl {
    qq(nose);
}

__END__
[download]

I hope i guessed right. Else sorry ;-) Best regards, Karl