How accurate is the counting? For examples like the case study, I presume your customers will want very close to 100% accuracy, but many other use cases will only need rough numbers. How do you calibrate / verify your app?
I can also imagine the new process have other benefits. Like before, if a customer complained of getting fewer than ordered pearls, they would probably have to acknowledge that as a counting error on their side but not knowing. Now they have a picture/data to refer back to.
At least that's how it is where I work; the automation leads to reduced errors, and when they happen the amount of data makes it easier to track where it went wrong.
It's also super easy to correct mistakes or to add items that are not visible in the image.
Possibly you're thinking of a single error rate across all customers? For other customers, as stated, it's not 100%. But taking an average across multiple customers is not meaningful when some are counting pearls and some are counting crops.