You don’t need to test every car every day, just like you don’t take your car into the shop every day to get the tread measured and the tires inspected. Cracks take a while to propagate. You just need to test them enough that you can catch them between when the crack is big enough to detect, but small enought that it won’t cause a catastrophic failure of the wheel. Most testing is done on an interval with a frequency less than the time it takes to fail (e.g. journals and rails).
The ad only mentions a ‘single’ carrier, measuring 100K data points - not all carriers. So to extrapolate that to the entirety if the rail network is in error.
Note - IE11 plays the IBM commercial - Firefox gives the skin error.
Ah! I had not noted the single carrier distinction… that does make a big difference, even if it were one of the largest ones that would inprove rate considerably.