The world of extreme sports is also one of the big businesses. Kids might think that snowboarding is the ultimate freedom, but this freedom is being marketed to them by commercial sponsors.

Extreme sports tricks are becoming increasingly complex, the courses ever more challenging and crashes all too common.

Some documentaries are made by people who are driven more by one particular story, or have different backgrounds or ambitions, but I'm always looking for projects that let me be the best filmmaker I can be, and to be stretched and grow further.

I remember when the Berlin Wall fell and suddenly intractable problems get solved.

I'm not an expert on how to configure the sport, but I can observe and say that accidents seem to be a part of it. The athletes are incredible, with the courage that they accept the risk of death, paralysis, and brain injury. These are really life-changing, life-threatening injuries, and the risk is extremely high.

I love great locations in movies, and I couldn't believe I'd never seen a landfill on screen before. It was the most haunting place.

I don't believe in objectivity. I observe the observer's paradox every moment I'm filming. Your presence is changing everything; there's no mistaking it. And you have a responsibility.