The formation of 一塌糊涂 is a vivid conceptual fusion where the concrete image of a single, catastrophic collapse ("一塌", one collapse) is seamlessly merged with the abstract state of a complete, indistinct mess ("糊涂", muddled confusion). This creates a powerful metaphorical compound where the visual finality and totality of a structural falling-down is used to intensify and pictorially define the extent of the disorder, transforming a physical scene into an expressive idiom for absolute chaos.