We examined potentially selective offloading decisions when the external store has a limited capacity and how the surprising unavailability of offloaded information influences subsequent offloading decision-making and memory. In three experiments, learners were presented with to-be-remembered words paired with point values counting towards their scores if recalled and were allowed to offload some words. Experiment 1 included only positively valued words, Experiment 2 included some negatively valued words, and Experiment 3 included only positively valued words but some extremely high-value words. Learners selectively offloaded high-value words (an ideal strategy if the external store is more reliable than memory) but were also selective in their memory for not-offloaded words. However, when offloaded words were surprisingly unavailable, learners frequently forgot high-value words, illustrating the potential dangers of offloading. Thus, offloading decisions should depend on the reliability of the external store, memory abilities, and the variability of the value of to-be-remembered information.