it's basically your face is a passports

so after you drop your bags you go through immigration so you go through this tunnel

and then if it's green that means you're registered and you're identified and you're all good to go however if it's red you will be stopped and will have to figure out why it it popped up as red

basically it will eliminate the the waiting area so and the boarding desk so no need for that it's just the tunnel that you go through