Octopus Deploy provides a system for scoping variables to different environments, roles, or machines, which is particularly useful for scenarios like using different database connection strings in Test versus Production environments. The concept of "variable specificity" in Octopus is akin to CSS specificity, where variables can be defined with multiple scopes, and the most specific scope takes precedence. This specificity is calculated through a ranking system that assigns scores based on the scope level, with machine-specific scopes being the most granular. Challenges arise when multiple scopes match a scenario, leading to potential non-deterministic outcomes, especially when roles overlap. The complexity of these specificity rules can make it difficult to intuitively understand which variable should apply, so it is suggested to model deployments in a way that avoids reliance on complex specificity matrices. Founder Paul Stovell highlights the importance of clarity in deployment modeling to prevent confusion for future users.