Which half? One day when I was a junior medical student, a very important Boston surgeon visited the school and delivered a great treatise on a large number of patients who had undergone successful operations for vascular reconstruction. At the end of the lecture, a young student at the back of the room timidly asked, "Do you have any controls?" Well the great surgeon drew himself up to his full height, hit the desk, and said, "Do you mean did I not operate on half of the patients?" The hall grew very quiet then. The voice at the back of the room hesitantly replied, "Yes, that's what I had in mind." Then the visitor's fist really came down as he thundered, "Of course not. That would have doomed half of them to their death!" God, it was quiet then, and one could scarcely hear the small voice ask, "Which half?" E.E. Peacock Jr., Seeing With Fresh Eyes science
What went wrong? If something ships from one of the companies I advise, and it is virtually unusable because of poor design (which as we all know occasionally does happen), you can bet I go directly to the designer and ask how this happened? It is absolutely on the designer to ensure this does not happen, so something went wrong. Similarly, if the product ships and performance is terrible you can bet I go directly to the tech lead with the same question. And most frequently of all, if something ships and the analytics show that it’s either not being bought or not being used, or it turns out that it violates some business constraint like compliance or privacy, you can bet I go right to the product manager with that question. Marty Cagan, Product vs. Feature Teams svpg.com Viability, usablity, feasibility