The so-called collapse of the wave function is still regarded as one of the central unresolved problems of quantum mechanics. This paper argues that this problem does not stem from an incomplete physical theory, but from a categorical misaddressing. The collapse is usually understood as a physical process that takes place within time and should, in principle, be further analyzable in dynamical terms. This assumption, however, is itself part of the problem.
On the basis of an ontological distinction between possibility and factuality, it is shown that the collapse is not a process, but an irreversible constriction of an ontological space of possibility. Measurement is not understood as an epistemic act, but as object-making: a coercion toward objectivity through which possibility is excluded and the world is fixed to a single factual continuation. The collapse does not mark a transition between states, but a boundary act at which the language of processes loses its validity.
In this understanding, the collapse is not an event in time, but a generator of time direction. Time appears as the trace of irreversible constrictions, not as a presupposed background parameter. The position advanced here thereby explains why the collapse cannot, in principle, be mechanistically explained without introducing additional entities or dynamics.
The paper proposes that the measurement problem should no longer be treated as a question of a hidden mechanism, but rather as a boundary phenomenon in which the ontological presuppositions of physical description themselves become visible. This shifts the focus from processes and mechanisms to conditions, regimes, and boundaries of world-formation.