Polyandry, or multiple mating by females with different males, is commonplace. One explanation is that females engage in convenience polyandry, mating multiple times to reduce the costs of sexual harassment. Although the logic underlying convenience polyandry is clear, and harassment often seems to influence mating outcomes, it has not been subjected to as thorough theoretical or empirical attention as other explanations for polyandry. We re-examine here convenience polyandry in the light of new studies demonstrating previously unconsidered benefits of polyandry. We suggest that true convenience polyandry is likely to be a fleeting phenomenon, even though it can profoundly shape mating-system evolution via potential feedback loops between resistance to males and the costs and benefits of mating. Convenience polyandry can occur when resistance is more costly than mating. When females do not benefit from polyandry it is sometimes suggested as being convenient. Convenience polyandry is rarely explicitly tested. New studies show cryptic benefits to females that negate convenience polyandry. Convenience polyandry may be a fleeting phenomenon that has the potential to shape mating system evolution. We provide a framework in which to test whether or not polyandry is convenient.