Model Software Delivery is an exercise in effectiveness, not efficiency.
Effectiveness is building the right software, for the right customer, with the right process, aligned with the current culture.
Efficiency is building software with as streamlined a process as possible for the current customer and in maybe in alignment with the current culture or in spite of it.
Business leaders will say they want efficiency but what they really need is effectiveness.
If you focus only on improving your team’s process (hello Scrum) you’re delivering efficiency gains, not effectiveness gains.
Scrum (and other agile methodologies) try to change your culture to deliver software effectively. Without that culture change, Scrum can only deliver marginal gains in efficiency, and no gains in effectiveness.
To deliver gains in effectiveness, your process and software must align with your culture.