title: Discord.js memberCount and members++ return different values
body: <p>Currently I'm developing a Discord bot function for counting users in guilds which are using my bot.
  Strangely I have noticed that countMembers and iterating through guild and increasing the members counter return different values</p>
  
  <pre><code>client.guilds.forEach((guild) =&gt; {
      var cnt = 0;
      console.log(guild.name + " " +guild['memberCount'])
      guild.members.forEach((member) =&gt; {
          cnt = cnt +1;
              if(member.presence.status == 'online' || member.presence.status == 'idle' || member.presence.status == 'dnd'){
                  var data = guild.name + ":@" + member.id + "\n";
                  fs.appendFile('guild-audit.txt', data, function (err) {
                    if (err) throw err;
                  }); 
              }else{
                  var data = guild.name + ":" + member.id + "\n";
                  fs.appendFile('guild-audit.txt', data, function (err) {
                    if (err) throw err;
                  }); 
              }
      })
      console.log(guild.name + " " + cnt.toString());
  })
  </code></pre>
  
  <p>For example:</p>
  
  <blockquote>
    <p>memberCount = GuildX 1596<br>
    cnt = GuildX 175<br><br>
    memberCount = GuildY 2385<br>
    cnt = GuildY 2365</p>
  </blockquote>
  
  <p>Where is the difference between memberCount and iterating through the members?
  I checked the documentation and in my opinion both should return the exact same value</p>