Bad implementation of custom views fields in Drupal 7

bad-drupal-7-views-field.php

<?php
/**
 * DO NOT USE THIS CODE
 *
 * Substituting custom field content in views hooks is a great way
 * to make enemies with future developers.
 */
function my_confusing_module_views_pre_render(&$view) {
  // This is messy and hard to understand for site builders and future developers.
  $view->result[0]->custom_field_999 = t('Foo');
}