When projectile spawned, timeline will start to animate. After 0.40 seconds, it will stop and we want to make same things after 1 second. That’s why we reconnected to delay. Now my question is why we created an event track. In event track we made node second to 0 so it will run at 0 seconds. So how timeline understands to run that event track when 0.40 second runs out? Because of this reason, I tried to do same thing with finished output. Because when timeline is finished when 0.40 second runs out, it will be finished and it will go to delay function. And it worked perfectly fine.
Why we used an event track rather than just finished output?
Is there a specific reason to use event track rather than finished output. Because this course is designed and implemented perfectly and professionally. So I think everything has a reason 
and there is a reason to use event track in this case.