Definitely agree that you should have validation if you can't guarantee the validity of your data, but I think there's a difference here. Coincidentally, I had

Definitely agree that you should have validation if you can't guarantee the validity of your data, but I think there's a difference here. Coincidentally, I had a discussion about a similar topic today. Basically how much validation is necessary and at what level should it be at? function add(a, b) if a is not a number throw error if b is not a number throw error result = a + b if result > max possible precise value throw error etc... I would never have these checks in a function that just added numbers if I could guarantee that any values passed to it are correct. The team in the article said that the config shouldn't return null so they didn't put checks before using that value. To me it seems like they missed necessary validation logic because they didn't the realize the full extend of the config.