User picture not removed when deleting user in Drupal 7
if you really like to delete user profile picture on user delete event use this code in hook_user_delete($account).

// Load user by using user id
$user = user_load($uid);
// Get file id of profile photo
$fid = $user-&gt;picture-&gt;fid;
// Load the file object
$file = file_load($fid);
// delete profile photo from.
file_delete($file);
// Unset the image object (my case it's 'picture')
unset($user-&gt;picture);
// Save the user
user_save($user);


hope works for you