The playback helps in to understand the candidate thought process. It gives you details of how the candidate code has evolved and results of each time the candidate had tried to test his code.

You can play the video of the coding question console that candidate has attempted.

To Playback the candidate code video. Go to the test takers, enable question wise report and open the HTML report of the candidate.  On the coding question, you will get the below screen to view the candidate code.

Refer the GIF Below:

By Clicking on the "View Compilation Result" button you would get just how well did the candidate do at that time.