The build-versus-buy question for ASR usually gets framed as accuracy versus convenience, but the real deciding factor is ROI over the lifetime of the product. Part 2 of the Whisper-to-in-house-ASR series makes that math explicit: what does it actually cost to fine-tune Whisper on your domain, host it, and maintain it — and where does that cost curve cross the line of paying a cloud API per minute?

The breakdown covers three angles that often get glossed over. On data, weakly labeled domain audio can move accuracy more than an equivalent budget spent on studio-quality recordings. On R&D, PEFT methods like LoRA plus off-the-shelf auto-fine-tune services shrink the engineering surface dramatically. On DevOps, the GPU cluster you think you need is usually smaller than the whiteboard estimate, especially with quantization and batching. If you're pitching an in-house ASR effort internally and need numbers to defend it — or you're being pitched one and want to sanity-check the assumptions — this segment is worth your time.