Against the claim that technological enhancements are largely good for us, I argue that instantaneous bypassing enhancements—enhancements that deprive the subject of opportunities for further self-development of that capacity—can be bad for us. Through an analysis of the existential phenomenology of Martin Heidegger and Maurice Merleau-Ponty, I show how human existence is temporally situated, and how our projections towards our future becoming imbue our experiences with value and significance. Because instantaneous bypassing enhancements disrupt the temporality of human existence, they would erase much of the value and significance in our lives that is gained through self-development. Moving beyond the binary of traditional and technological enhancements, I offer a more substantive framework for analyzing enhancements in regard to how those enhancements affect temporal self-development. I also respond to various claims made by proponents of transhumanist enhancement like Nick Bostrom and Julian Savulescu, arguing that there are important differences between particular categories of traditional and technological enhancements, that it is impossible to enhance self-development through instantaneous bypassing enhancements, and distinguishing how my analysis differs from boredom arguments. Moreover, I argue that all forms of instantaneous enhancements foster an inauthentic or anonymous mode of being.