Why is the region not displayed?

Question

Drupal

Why might the region (block) not be displayed on the site?

How to trace all the way from base to template?

# sites/all/themes/pa/templates/page.tpl.php
  <?php if ($page['content_bottom']) : ?>
    <div id="content-bottom" class="container">
      <?php print render($page['content_bottom']) ?>
    </div>
  <?php endif ?>

# print_r($page)
    [content_top] => Array
        (
        )

    [content_bottom] => Array
        (
        )

    [sidebar_first] => Array
        (
        )

    [scroll_content] => Array
        (
        )

    [scroll_menu] => Array
        (
        )

Answer 1

There are no results in views.
No rights to view views.
No rights to view the block.
No rights to view content.
The block contains the visibility settings.