Part of the issue is that people seek out risk. If something is made safer, people will not go "great, no we're not taking any risks" - they will seek out something riskier.

Peoples individual risk tolerance varies, but we all tend to have a tendency to see a reduced risk as a reason to push things further.

This gives rise to the situation where if we make changes that are perceived as adding more safety than it actually does, we even risk actually causing more injury than we prevent