It depends. Imagine a hardware device that uses the speech API, and you're looking at the 3 year cost of an average of 5 speech interactions per day (something like the Amazon Echo). Using Nuance pricing of $0.008/request, you're adding 365 * 3 * 5 * $.008 = $43.80 in cost above the BOM cost; It's entirely possible that adding $20 to the BOM is viable, but adding $40 is not.