I think it's a very common misconception among programmers that the law is a sort of natural language 'program' where you can consistently deduce that x input generate y output.
It sort of is, except that the entire law isn't defined in one place. "Hey, do I have a home office?" Well, "home" is defined over in this regulation, and "home office" is defined over there in that other regulation, and "having a home office" would normally mean this except for this case law that says it can also mean that when these other circumstances apply, and...
These things are knowable, but unless you've spent some time studying it intensely, it's certain that you only know a fraction of the places where the program is written.
If it's helpful, programmers should imagine that it's written in C. At a glance you can tell what something's doing, but once you study it you can find UB all over the place and suddenly it's hard to say what the right answer is until you know the intricacies of the compiler and the target platform. You can't really determine the exact behavior without all that information that lives outside the code. Now, once you have all that, you can surely reason through it all. But how many people actually know all that, or even realize which parts they don't know?
"This is pretty straightforward" is a sure sign of someone who doesn't actually understand it well.
A point echoed by Nilay Patel (who used to be a law professional) here https://www.theverge.com/podcast/917029/software-brain-ai-ba...