Architectures which are based on a fixed decision cycle are usually concerned with real time constraints. Decision cycles are analogous to fetch execute cycles of standard computer architectures. They normally require the choice and execution of a simple operation, possibly one step of a plan, in a fixed amount of time or with a fixed amount of quality. One example of such a cycle is the 'satisficing cycle' in the system, by . Another is the deliberation cycle in the architecture, by .