Horsepower figures are insane these days! The news of a new 350 horsepower sedan (Saloon, if you must) is usually followed by a "Meh" or just slightly more air exhaled through people's nose. They casually shrug their shoulders, "Impress me!" they say, as the thought of a 0-60 mph of 5 seconds warrants a 'Ain't nobody got time for that' meme.
What people don't fully appreciate is the hundreds of thousands of man-hours dedicated to the sheer design, development, and testing of these extremely capable cars. In this documentary about the development of the Bugatti Chiron, it shows the immense amount of over-engineering that goes behind developing something that can do up to 420 kph.