In R, a Factor is also the bizarre result you get if you load a flat file incorrectly. Lots of things in R proceed without stopping on errors, and you end up with weird data that isn't really usable but still lets your program continue.
I'm not sure what that means, because a default R installation will always stop on an error.
> a Factor is also the bizarre result you get if you load a flat file incorrectly
That's user error. No programming language can catch that - it can only detect errors that are defined as errors.
People using default R installations report that special commands are needed to make it stop on all errors. Are they delusional? What about the R experts who give them solutions, are they doling out placebos?
This alone would make me run away very fast from R.