How does Keller's interest conflict with the common good of society and produce dire consequences for another member of society?

I'm going to assume that you are referring to the whole faulty airline parts thing. Keller wants to save money for his business so he cuts corners. When the airplanes crash and pilots are killed he puts the blame on Steve. So Keller causes the death of something like 20 fighter pilots (the good of society is seriously betrayed here) and puts the blame on poor Steve who did not want to weld over the cracks in the first place. Steve is sent to jail because Keller claims that the phone call (telling Steve to cover and send faulty parts) never took place. I hope I have the right part you are looking for.