I have the following business logic collection hook. 

function onPostSave(request, response, modules) {
  var logger = modules.logger;
  if (request.body.Barcode === "None") {
    logger.info(request);
    var collectionAccess = modules.collectionAccess;
    collectionAccess.collection('user').find({ "username": modules.requestContext.getAuthenticatedUsername() }, function (err, userColl) {
      if (err) {
        logger.error('Query failed: ' + err);
      } else {
        logger.info('Query success: ' + JSON.stringify(userColl));
        logger.info(JSON.stringify(userColl));
        modules.email.send('no-reply@slyk.com',
          'michaelvowles571@gmail.com',
          'Asset Tag notification',
          'Asset tag needed for ' + userColl[0].Company +
          ', e: ' + userColl[0].email +
          ' p: ' + userColl[0].ContactNumber + '. Asset _id:' + response.body._id +
          ' Asset name: ' + response.body.AssetName +
          ' Asset OEM: ' + response.body.OEM,
          function (err, result) {
            if (err)
              logger.error(err);
            response.continue();
          });
      }
    });
  }
  response.continue();
}

 If I remove the `logger` call on the fourth line the script no longer works. However leaving it in makes it work how is this so?