That depends on how many details I specify. If I specify a lot, I usually get what I want. But in the extreme this is just another form of coding (high quality code is quite similar to a detailed spec). In many cases I find I have to do many "passes" to get the right balance of correctness, performance, security, and clean architectural boundaries. Having a loop to fix these often makes it worse since they can often be contradictory.

There's also some types of code that I believe is often wrong in the training data that is almost always wrong in the LLM output as well. Typically anything that should have been a state machine, like auth flows, wizards, etc.

When all is said and done I think the main savings come from the high throughput of low-value generic solutions. I don't currently see this changing, and the reason is that high quality products cannot be generated without specifying a lot of details. Of course, we may not want quality.