One of the features built into the Triggertrap, is that you can specify a delay between the Triggertrap sensing an event (say, a laser beam being broken, or a change in light for the Triggertrap V1, or a sound, or motion being detected for Triggertrap Mobile), and the trigger signal being sent to the Triggertrap. There's a few reasons for this, but the most important one is that you may not want to trigger your camera immediately when something happens. For example, if you are trying to take photos of droplet hitting a glass of water, you may want to place the laser you use to measure the event above the glass, so the laser itself won't be in the picture. Obviously, the droplet still has to fall for another couple of inches, and that necessitates a delay.
Similarly, I tried to use the sound sensor to take a photo of me chopping a quail egg in half with a hatchet. Without a delay, the photos were certainly not very dramatic. Of course, I ran out of quail eggs before I got the timing right, but that's a blog post for another day :)