Non-determinism means here that with same inputs, same prompts we are not guaranteed the same results.
This turns writing code this way into a tedious procedure that may not even work exactly the same way every time.
You should ask yourself, too: if you already have to spend so much time to prepare various tests (can’t trust LLM to make them, or have to describe it so many details), so much time describing what you need, then hand holding the model, all to get mediocre code that you may not be able to reproduce with the same model tomorrow - what’s the point?
This turns writing code this way into a tedious procedure that may not even work exactly the same way every time.
You should ask yourself, too: if you already have to spend so much time to prepare various tests (can’t trust LLM to make them, or have to describe it so many details), so much time describing what you need, then hand holding the model, all to get mediocre code that you may not be able to reproduce with the same model tomorrow - what’s the point?