my $found = 0;
...
if ($found == 0){...

# or better:

if (! $found){...

# or for truth:

if ($found){...

##</code><code>##

use warnings;
use strict;

my $organization = "thre";

my @orgs = qw (one two three four);

error_suspect_org() if ! grep {$organization eq $_} @orgs;

sub error_suspect_org {
    die "not a valid org!\n";
}