Why does the order in which handlers are linked together in a Chain of Responsibility matter more than layering order typically does when stacking purely additive behavior?

When behavior is purely additive -- each layer only adds something on top of what came before, without changing whether processing continues -- the final combined effect is often the same regardless of stacking order. Chain of Responsibility is different because each handler makes an actual routing decision: it decides whether to handle a request outright or pass it along, and that decision can depend on the request's specific properties. Putting a specialized handler earlier in the chain means it sees requests first and may intercept ones a later, more general handler would have processed differently, or vice versa. Because the outcome for a given request can genuinely change based on which handler encounters it first, assembling the chain in the right order is a real design decision that deserves as much attention as writing each handler's internal logic.