Code is a project that has to be updated, fixed, etc.
So when something breaks - you have to ask the contractor again. It may not find an issue, or mess things up when it tries to fix it making project useless, etc.
Its more like a car. Every time something goes wrong you will pay for it - sometimes it will get back in even worse shape (no refunds though), sometimes it will cost you x100 because there is nothing you can do, you need it and you can't manage it on your own.
LLM outputs are akin to a mutant tree that can decide to randomly sprout a giant mushroom instead of a branch. And you won't have any idea why despite your input parameters being deterministic.