I am an engineer, but in my experience the engineers shouldn't be driving product development. The companies I have worked for were the product specs were driven by the engineers produced technically cool products but they were so expensive that no one wanted to buy them. The prospective customer reaction upon hearing the price was usually, "You are joking, right?" The most successful company I worked for had marketing people with engineering backgrounds and negotiated product specs with engineering. This addressed market needs tempered with feasibility. GM's problem is either incompetent marketing people and/or government interference producing product for government goals/ideology.