If You Don't Know The Track You Might Get Into A 200 KM/H Crash Like This Guy
Maybe memorize the track before you hurt yourself
Racing on a public road that's been converted into a track must be a pretty awesome feeling. Knowing that the plebes would normally use these roads on their way to work and trudging through it at a miserable pace, while you bomb down a straight knowing there's no traffic to ruin your day. It's just you, a closed track, and your driving skills.
The thing about public roads though is that it is shaped FOR the public. You'll run into T-intersections, crowned road surfaces, and plenty of turns. Features that for normal traffic seem like a reasonable amount of space to travel through, however, when you're racing through it at a high rate of speed, you'll need a high level of precision, racing know how, and sometimes luck.
In the case of this Audi RS3 driver racing through Circuit de Chimay in Belgium, they probably didn't know the layout of the track. After flying down the straight at 200 KM/H, the slight uphill and partially blind T-intersection, was too sharp of a turn at the speed the driver was travelling. Had they recognized that there was a sharp 90 degree turn shortly after the uphill, they could have still had a fully operational Audi RS3 in their possession.