title: Destroy Anchors in Unity ARCore
body: <p>I have a project that places a game object on the position a user touches the screen. An anchor is made as such:</p>
  
  <pre><code>private Anchor anchor;
  
  anchor = detectedPlane.CreateAnchor (new Pose (anchorPosition, Quaternion.identity));
  
  transform.position = anchorPosition;
  
  transform.SetParent (anchor.transform);
  </code></pre>
  
  <p>Right before creating an anchor when a user touches the screen the second time or any number of times after that, I make sure to destroy the anchor with the following code.</p>
  
  <pre><code>if (anchor != null) {
      Destroy(anchor);
  }
  </code></pre>
  
  <p>However, when I test my code on Instant Preview, all of the anchors remain after I touch the screen multiple times. Is this the right way of destroying anchors?</p>