How the heck do people get their hair so straight with the chi?

my hair is curly every hair straightener i've had made my hair turn wavy so i bought the chi and it still turns my hair wavy! i'm like wth???? people use the chi and their hair is a lot curlier and it gets their hair COMPLETELY straight! and i've used everything in the steps of straightening my hair, a blow dryer, chi iron guard, and redken power tame. and yet my hair STILL turns wavy!! what do i do to make it so straight? thanks!