A young engineer on my team wanted to skip a redundancy to hit the cost target, and I walked him through the day I stopped thinking of safety factors as waste. I design assuming I'm not smart enough to foresee every failure, and I build in the margin for the people who'll never know my name. The extra work is the whole point of the job, and I do it every single time.
More people experience this than they realize.
You design humbly for unforeseen failure, holding the safety of unseen people as the point of the work.
If this sounds familiar, the Library can help you find the bigger picture.