THE KIAI
The kiai, has multiple purposes.
Kiai acts as a declaration of your fighting spirit, your internal desire to prevail in those circumstances. This can be for intimidation, or self-reassurance.
The Kiai is an expulsion of intent focusing on the target and breath, one is less inclined to focus on fear or failure especially when breaking something hard. eg wood or brick.
The external harmonizing of ki energy (気合 - kiai).
The Kiai is a great tool for switching into defense or offence mode.
In a confrontation people can be in a state of shock and freeze up. The Kiai can wake you from the freeze state and get your defenses and awareness up.
A test done with students at Jo Taekwondo proved that they kicked harder and faster after they kiai.
The benefit of the Kiah with shy students is that they find their voice, some students are immensely shy to the point that its debilitating they are scared to speak up and speak out, the Kiai helps students get comfortable with their voice in a supportive group environment.
We focus on the loud Kiai at Jo Taekwondo the video is a good reference for the technique.

