What are common pitfalls or gotchas with best practices (Modern Perl)?

# Common pitfalls in Modern Perl

# 1. Not using strict and warnings
use strict;
use warnings;

# 2. Relying on global variables
my $global_var;

# 3. Not following the object-oriented paradigm
{
    package MyClass;
    
    sub new {
        my ($class) = @_;
        my $self = {};
        bless $self, $class;
        return $self;
    }
  
    sub my_method {
        my ($self) = @_;
        # Method implementation
    }
}

# 4. Ignoring error handling
open(my $fh, '<', 'file.txt') or die "Could not open file: $!";