The idea is that, for the rich, a normal speeding fine isn't much of a disuasion, so they tend to become repeat offenders—unless the fine really bites hard.
With fines of 2,000+ CHF a day, even the mega-wealthy start to pay attention.
https://www.theguardian.com/world/2010/aug/12/record-speeding-fine-switzerland
The key to enforcement is that in Switzerland, you own your license plate. Replace your car, and the plate goes on the new car. Unless you change cantons (and few people do), the plate is yours for life.
It's a permanent record—which makes enforcement of speeding laws easier. The first two letters indicate the canton you live in (in this case, #Zürich.)