[throwaway_ghj]

  * they are part of a big enough team that individual responsibility is removed
  * they're not given enough time to produce good quality code
  * the design came from someone without sufficient expertise, and the programmers "just built it"
  * they did the best given the time they had
  * it passed testing
  * programmers are generally not empowered to make go/no-go decisions
  * even if they did express concern they may not have been listened to
  * any internal challenges on ethical grounds were probably kept quiet and worked around

Usually with this kind of incident there are multiple process and quality failures, not just "why did the programmers not do better"

[jack9]

I have always objected when software was designed against my own ethics. I was never forced out, I just got another job or worked on another project. Every developer asks the question "why" am I making this. Only developers who care about the product seem to dig when given a hand wave and not a lot of them seem to care.

[throwaway_ghj]

Is it ethical to just walk away from a problem?

[jack9]

Is it a problem that people commission unethical things? If it was a danger to human life, I'd have to drop an anonymous note to a newspaper and regulatory body or two.