A stochastic discrete model is offered that simulates the behavior of particulate composites able to generate and accumulate scattered structural microdamages to the final breakdown of the model. The model is quite transparent, which allows us to observe continuously its internal state and effective behavior, Through numerical experiments, it is established that the accumulation of the scattered damage, accompanied by the appearance of the elastic nonuniformity, ends in a loss of the elastic stability of the whole of system and macrocrack formation in the most compliant part of the body. No strength criteria are needed to describe this process. Breaking stresses and strains and their scatter in repeated experiments, as functions of the virgin system specification, can be calculated and used for safety factors or for optimization of composite properties.