Accuracy is a measure how closely your product meets a specified standard or criteria. Precision is a measure how reproducible your results are, whether your product performs consistently across a group of customers. The FDA tries to optimize quality of medical devices by focusing on these two aspects of a product. If a product performs inaccurately, then no one will buy the product and this will hurt the business. It will also hurt the business if the desired result isn’t reproduced across most scenarios. It won’t matter if the product can performed ideally because more than person is buying this product, so it has to be consistent in maintaining that standard when people use it. Ideally, the product will be both accurate and precise in performance. However, this is a difficult task that many companies struggle with, which is why they have employers who do risk/error analysis on their products to find ways to lower the amount of defects in their products by changing an aspect of a process of some external factor.