Objective measurements don't define what you'll get from any headphone. In the end, it depends on so many factors, such as 1) what you're listening with, 2) the way the album/song was produced and those EQ settings, 3) how you perceive sound personally/subjectively, 4) and the quality of the audio file/source itself. Any of these combinations will "color" the sound. Even if you have 100% "neutral" headphones, it doesn't mean that all your equipment will present every single album with complete neutrality. Some albums might work best with the most neutral headphone, while another song or album will not be as engaging or exciting. A remaster of an album will have something else about the way it is mixed that isn't the same as the previous release. Having several headphones, and more than one DAC, DAP and/or amplifier allows the opportunity to discover what works and what doesn't work, not just from album to album, but from song to song. If you only listen to one type of music, that could make it easier to streamline your gear. If all headphones were completely neutral and had the exact same measurements, then why does one "neutral" headphone STILL sound different from another? Part of the fun with this hobby, for me, is discovering music from a different avenue of approach. Sometimes, I just want to lay back, relax, and let music entertain me. Other times, I like it when I can discover little details in music I never noticed before, influenced by any of the countless combinations of the audio chain going up to my ears (including volume level). In my opinion, there is no "One Headphone To Rule Them All".