The paper explores the creation of mobility edges (ME) and enhancement of localization in quasicrystals due to pure dephasing effects. Despite the common belief that dephasing and decoherence typically destroy Anderson localization and enhance transport, the study demonstrates that ME can be induced by dephasing in systems where all states are initially delocalized. The key findings are illustrated using the off-diagonal Aubry-André model, where dephasing creates ME and slows down the delocalization of excitation in the lattice. The results are further supported by numerical simulations and a photonic quantum walk setup in synthetic quasicrystal lattices, which provide an experimentally accessible platform for observing these phenomena. The study reveals a novel mechanism for ME formation and suggests that dephasing can paradoxically slow down transport in disordered systems, challenging conventional wisdom.The paper explores the creation of mobility edges (ME) and enhancement of localization in quasicrystals due to pure dephasing effects. Despite the common belief that dephasing and decoherence typically destroy Anderson localization and enhance transport, the study demonstrates that ME can be induced by dephasing in systems where all states are initially delocalized. The key findings are illustrated using the off-diagonal Aubry-André model, where dephasing creates ME and slows down the delocalization of excitation in the lattice. The results are further supported by numerical simulations and a photonic quantum walk setup in synthetic quasicrystal lattices, which provide an experimentally accessible platform for observing these phenomena. The study reveals a novel mechanism for ME formation and suggests that dephasing can paradoxically slow down transport in disordered systems, challenging conventional wisdom.