At the very least, this provides a framework within which mutual trust can be pursued, whatever the difficulty of the times. But it is especially useful in a crisis.
It has repeatedly proven its value when there is a recognised, urgent need to provide coordinated responses, as happened in 2008-9, and occurred again in the last couple of years, including in 2021, when the G20 acted to secure funds for vaccines and suspend the debt service for the most vulnerable economies.