We don't say "perfection is impossible" when it comes to bridges collapsing. We understand that yes, on rare occasion a bridge WILL collapse, but we go and find the people responsible, and we still hold them accountable.
This is a level of accountability that basically every other field of engineering is held to, and they've all risen to the challenge and left the "off-brand duct tape" behind.
Even within programming, planes don't fall out of the sky daily, so I feel safe assume the aerospace programmers are comfortable working with a high degree of responsibility. High speed traders are dealing with million-dollar stakes and a single mistake can make the news. I'd expect they've got a very accountable culture where people get fired when that happens.
There are costs, yes, but there's also costs to keep 733 people illegally imprisoned - we're talking two man-years of peoples lives lost every DAY this goes on.
