What is the real price of one successful line of code?

Every line of code has its own story that is far way beyond than commits in Git repository. In fact it is result of problems, decisions, communications, compromises and solutions achieved not only by engineers, but also end users, business analysts, stakeholders, support, auditors, project managers. During the session we will track the journey of a line of code through its entire lifecycle starting from idea to improve the world, compiling requirements, designing solution, creating implementation plan, dev team tasks planning, development, quality control, release coordination, production monitoring, maintenance and finishing with audit. The main question we will look an answer for - how to write the code that would be efficient on all of these phases and as a result would generate more revenue rather than costs?