I never understood the point of manual test scripts. They annoy me. I view them as nothing more than a candidate for automation. I have never come across a manual script that wouldn’t be better used as an automation script, which of course violates the inherent nature of them being manual test scripts. The only value to manual test scripts is to give them to clients, so that they can run through the new app you just created for them and feel comfortable about the application (and learn about the app as they run through the scripts).
Jonathan Kohl presents the perfect argument about why manual test cases should be extinct. Everyone should read this. Developers should read it, clients should read it, testers should read this, and, most definitely, project managers should read this.
Most bugs will never be found by a manual script. They only illustrate the “conventional” click-path for completing a task, and the developer should have already went through this during their own testing; there is high probability that this path will already work. End-users are never going to follow this path, anyway; they will do something that you entirely don’t expect. They will hit the ‘Back’ button when you didn’t plan for it, or double-click the ‘Submit’ button when you didn’t handle it, or bookmark the third step in a five-step wizard. Scenarios like these will never be tested in a manual script, but could be tested if so much of the industry wasn’t convinced that scripts are the holy grail, and will be tested by any tester worth his salt.