Most communication, discussions, and thinking tend to focus on the solution level. You and your co-worker might discuss what the ideal next step should be, losing yourselves in endless theoretical discussions about solutions.
The problem is that energy spent at this level is typically wasted. Instead, it's better to focus on the problem level. This means understanding the core issue thoroughly and ensuring everyone has the same data and facts - eliminating any divergence in implicit assumptions.
From my experience, when you spend enough time working on the problem level, the solution often becomes obvious. Rarely do people disagree on a solution if they have the same understanding of the problem. However, if disagreements persist, it typically indicates that the problem is not understood in the same way by everyone. In such cases, energy should be focused on aligning this understanding.