This study tested the hypothesis that the paradoxical effect of ease of retrieval via unintentional recall is due to an effortful recall strategy. In two experiments, participants memorized a list of positive and negative behaviors that had been performed by others. Subsequently, the participants were asked to recall either one or four positive behaviors (i.e., easy vs. difficult recall). In Experiment 1, the dual task method was used to manipulate the participants’ cognitive load during the recall task. When the participants experienced recall difficulties in the no-load conditions, their judgments about others contradicted the recalled information. These effects were mediated by the unintentional recall of negative items. In the loaded conditions, this pattern was not observed. In Experiment 2, unintentional recall only facilitated memory retrieval in the participants with strong motivation (“a need for cognition”) to perform the task. These results suggest that effortful processing is used to aid memory retrieval when recall is difficult. When the recall of positive items is difficult, the associative memory is exhaustively searched, and judgments are formed based on information that is unintentionally recalled during this process.