It's an idea from decision-making theory. A maximizer would try to review all possible options, then select the best one; a satisficer would evaluate each option in turn, then select the first one which meets their criteria.
It's a way of looking at rational decision-making which accommodates the fact that information is incomplete and time is a factor; the optimal choice may not be the maximal one, because the cost of evaluating the options must be factored into the decision.