Majorana fermions, particles that are their own antiparticles, have attracted significant attention in condensed matter physics due to their exotic properties and potential applications in fault-tolerant topological quantum computing. Although nanowire-superconductor hybrid systems and topological insulator-superconductor heterostructures, are considered the most promising platforms for realizing Majorana fermions, recent experimental progress has been overshadowed by controversies, including the retraction of several high-profile papers claiming their observation. These controversies fundamentally originate from experimental data being selectively presented to conform to oversimplified theoretical models. Traditional phenomenological approaches, which model Majorana fermions through simplified effective Hamiltonians, neglect crucial experimental complexities such as quasiparticle excitations in superconductors and the effects of strong proximity tunneling and high magnetic fields. Consequently, they fail to predict the correct parameter regimes for Majorana Fermion emergence in realistic devices, leading to false-positive signals in experiments. To overcome these challenges, we formulate a unified“dressed Majorana” theory that treats both the electrons in a nanowire and the superconducting quasiparticle excitations on an equal footing. Our results reveal the stringent conditions necessary for the realization of Majorana fermions: the precise alignment of chemical potentials (within ~1 meV in a 1 eV tuning range), and the careful control of tunneling strength and magnetic field strengths. These findings explain the persistent absence of definitive signatures in experiments and provide quantitative guidelines for future studies. Notably, for alternative platforms like quantum dot-based “poor man’s Majorana” systems, our analysis shows that the obtained Majorana wavefunctions are localized at both ends of the superconductor, demonstrating the essential role of the superconducting component in these configurations. In summary, our study not only clarifies the current controversies surrounding the detection of Majorana fermions but also establishes a robust theoretical foundation guiding future experimental efforts toward unambiguous observation of Majorana Fermions.