"Does your software work?" is almost impossible to answer objectively, and doesn't help you determine if the software is going to work 2 years from now (which a good deal of development best practices work to achieve). You might as well replace the test with "Is this company awesome?"
In some areas of software development, such as heavy duty algorithmic/mathematical programs such as encryption, video compression, computer graphics, there are pretty rigorous objective ways to measure whether the program works and how well, without human testers or QA people. Usually best to do both even in these cases, just in case there are some subtle issues that the performance metrics don't capture.
On the other hand, predicting the future is noted for being rather hard. Predicting correctly whether a program will need to be changed in two years, in what way, and whether the program can in fact be changed easily all two years in the future is speculation, a matter of opinion, rarely objective at all.
For the majority of business facing SaaS applications (to name an example), "working" is an elusive target. If we gave it to those pesky end users, and there's more than 5 of them, I guarantee you'd hear multiple answers to how well it works certainly, and even if it works.
I'm not saying that looking at how well your product works for people isn't a noble endeavour or anything. For the purpose of what this is supposed to be - an easily obtainable, objective measure of what it's like to work for a company, it's horrible.
A well functioning development team is wonderful...for developers.