Given the line of argument, Microsoft should make Vista bug free and do away with 95, 98, Me, 2000 and XP. And there should really be only one colour of cars available, just to standardize.
There is no such thing as a completion of R&D. It is a continuous process, as there is always room for improvement. It does not make business sense to wait until a perfect product is conceptualize before rolling to market. What is normally done is that test cases are drawn up to ensure that the product works fine under REASONABLE conditions with REASONABLE consumer expectations.
I distinctly remembered that some time back there was a brand of addictives that had left out sealing the bottles. And it is after the good feedback from the users that it was rectified.
But I am sure the manufacturers will nevertheless take this feedback and consider it carefully.