The result of DevOps implementation is not only greater success of the process, but greater teamwork. Give up the blaming, and focus instead on the customer experience. Like any transformational journey, it starts with the people, all aligned on a vision for the future.
A lack of understanding of technical debt and its consequences can slow progress to faster cycle time and improved quality. By discussing debt, its consequences, and how it can be reduced, you can create a culture in which improvement is a focus, and your investment in improvement pays off.
Most teams never explicitly state how they commit to working together. They just start working and may eventually get better.
If there is clear alignment on the business goals you'd like to achieve & the measures of success, that will help you persevere when progress becomes difficult.