I'm still waiting till the promise of voice AI that was showed during the OpenAI demo in 2024 turn real somehow. It's not clear to me, why there has been zero progress since then.
Cloud hosted models definitely can not always be consistent, but it's where I'm learning that prompt durability is a thing.
It is an adjustment coming from deterministic software and adding non-deterministic software to it, which can be improved by the quality of language and input into it.