Sensory perception of environmental cues has been shown to trigger plastic responses that can induce important fitness costs, including the dramatic modulation of ageing across distant taxa. For example, male Drosophila melanogaster suffer a marked decrease in fitness, including faster reproductive and actuarial ageing, if they perceive female cues but fail to mate shortly after (ageing via sexual perception). While this has been a breakthrough for our understanding of the mechanisms of ageing, it poses the question as to why such plastic responses evolved. Here, we used D. melanogaster to ask whether sexual perception costs may be a by-product of plastic adaptive responses to female cues. We found that: a) short-term (1 day) perception of female cues prior to mating opportunities increases male relative lifetime reproductive success in a competitive environment, b) medium-term (3-7 days) perception is neutral, and c) long-term (15 days) perception leads to reproductive costs. We then ran mathematical simulations under a wide range of socio-sexual and demographic scenarios to show that such plastic male responses can be adaptive whenever mating rates fluctuate within the range experienced by D. melanogaster and other insects in the wild, suggesting this may be a widespread strategy in nature. Finally, we show that, because the short-term benefits of plastic responses will be mostly acquired by high-quality males while long-term costs will be mostly paid by low-quality males, sexual perception can significantly magnify sexual selection (15-27% average increase in the opportunity for selection).