diff --git a/core/includes/install.core.inc b/core/includes/install.core.inc
index a90529494f..39f15149a3 100644
--- a/core/includes/install.core.inc
+++ b/core/includes/install.core.inc
@@ -1268,10 +1268,13 @@ function install_select_profile(&$install_state) {
 }
 
 /**
- * Determines whether or not to automatically install a profile by default.
+ * Determines the installation profile to use in the installer.
  *
- * Under certain conditions (listed below), a default profile will be selected
- * (and subsequently installed) without allowing the user to choose a profile.
+ * Depending on the context from which it's being called, this method
+ * may be used to:
+ * - Automatically select a profile under certain conditions.
+ * - Indicate which profile has already been selected.
+ * - Indicate that a profile still needs to be selected.
  *
  * A profile will be selected in the following order of conditions:
  * - Only one profile is available.
@@ -1282,8 +1285,7 @@ function install_select_profile(&$install_state) {
  *   distributions, then the first discovered profile will be selected.
  * - Only one visible profile is available.
  *
- * If NULL is returned (a profile has not been selected), then the interactive
- * installer will allow the selection of one of the visible profiles.
+ * If none of the above conditions are met, then this method will return NULL.
  *
  * @param array $install_state
  *   The current installer state, containing a 'profiles' key, which is an
@@ -1292,32 +1294,34 @@ function install_select_profile(&$install_state) {
  * @return string|null
  *   The machine-readable name of the selected profile or NULL if no profile was
  *   selected.
+ *
+ *  @see install_select_profile()
  */
 function _install_select_profile(&$install_state) {
-  // Don't need to choose profile if only one available.
+  // If there is only one profile available it will always be the one selected.
   if (count($install_state['profiles']) == 1) {
     return key($install_state['profiles']);
   }
+  // If a valid profile has already been selected, return the selection.
   if (!empty($install_state['parameters']['profile'])) {
     $profile = $install_state['parameters']['profile'];
     if (isset($install_state['profiles'][$profile])) {
       return $profile;
     }
   }
-  // Check for a distribution profile.
+  // If any of the profiles are distribution profiles, return the first one.
   foreach ($install_state['profiles'] as $profile) {
     $profile_info = install_profile_info($profile->getName());
     if (!empty($profile_info['distribution'])) {
       return $profile->getName();
     }
   }
-
   // Get all visible (not hidden) profiles.
   $visible_profiles = array_filter($install_state['profiles'], function ($profile) {
     $profile_info = install_profile_info($profile->getName());
     return !isset($profile_info['hidden']) || !$profile_info['hidden'];
   });
-
+  // If there is only one visible profile, return it.
   if (count($visible_profiles) == 1) {
     return (key($visible_profiles));
   }