The student must be very comfortable in the water and will need help getting back out to the break. It's not gonna happen overnight. A lot of it depends on your innate ability, the amount of time you practice and your sense of fearlessness. Maybe you ran into a bush or two. It was probably some time after that that you felt comfortable doing things like taking your hands off the handlebars, jumping curbs, etc.
Big waves take a heck of a long time to master.
It all takes time and practice. Yes, Maui has sharks, and the rare shark attack, albeit far fewer than say California or Australia. It's not a regular occurance though. It happens every day. There's a lot to consider when you are on the ocean and dealing with water and fiberglass surf boards.