It's normal for young engineers to believe they can write code that cannot fail, design parts that cannot fail, design bridges that cannot fall down, etc. Fortunately, it was beaten into me in my first job that the idea is not to create designs that cannot fail, but to create designs that can tolerate failure. It's a very different mindset.
>>Walter+(OP)
Unfortunately I don't think this is being beaten out of people these days. I meet plenty of people that are seniors at quite reputable companies that believe that and it scares me...