Special attention is paid to industries such as construction or aerospace, as safety and reliability must be ensured. Regular checks to ensure that welds on stainless steel pipes and containers are in good order or that the aluminum structure on aircrafts is at risk of fatigue are essential for survival. Material failure can have fatal, irreversible consequences. Therefore, the rule is: trust is good - control is better! This also applies to the gold industry, among others. Do not be deceived by appearances. Even if the gold coating still shines so beautifully. If the core is made of copper, as seen in a huge fraud scandal in China, this can have drastic economic consequences.