Ok let's debate. When we talk about safety, we r referring to a system not just one piece. Car design is one piece and u r rite, it's not designed to survive a crash at 100km/hr.
Design is only one part of the safety equation. How the part is manufactured plays a much larger part in the overall outcome.
Let me give you the best example regarding how safety is compromised for the average consumer.
I used to work in manufacturing. For consumer grade components, we took samples using an AQL of 0.1% to inspect for quality.
However for military grade products we did 100% inspection. Military grade components were 10 times more expensive because of the additional overheads but they had a huge budget and were willing to pay.
This means that regardless of how the component was designed, we knew full well that when it came to consumer products, some would fail as a result of manufacturing defects because we never tested the whole lot. Many went out the door with the manufacturer knowing full well that they were defective.
Safety has become more and more important as the years have gone by but the principle is still the same. Manufacturing has to fit into an overall business budget and it simply impossible to inspect everything for every possible criteria for consumer grade stuff.
Defects will ultimately cause systems to fail and result in injuries and death but it is cheaper for companies to compensate accident victims than it is to manufacture products where safety ranks above all else.
Same applies to the airline industry. When a crash occurs airlines payout millions but it would cost them probably 10 times the amount to reduce the crash rate by 50%. An accountant and a risk assessor does the sums and a decision is made accordingly. It is always a business decision not a safety decision.