The movies themselves back up that image of an actor obsessed with the tension between the hardened exterior and soulful interior life. The woodsy glamour of Last of the Mohicans, the studied propriety of Age of Innocence, and the rugged desperation of The Crucible all show off this tendency. Even his take on Abraham Lincoln, a historical figure practically weighed down with pre-conceptions, was both oddly funny and deeply melancholy, complicating the public perception of the man. The collaborative nature of his relationships with directors like Jim Sheridan, Martin Scorsese, and Paul Thomas Anderson only adds to the mystique. Retiring early provides another layer of mystery.
For other performers, retiring far too early in a career is often interpreted as an act of either cowardice or arrogance. Why walk away from true greatness? You really don't think you can make anything else worthwhile? It's a point of view that's reflective of the underlying entitlement driving most fan-artist relationships: We always want more, more, more. For decades, Day-Lewis was virtually peerless because he provided more enigmas, more accents, more emotions, and more hairstyles than his contemporaries. (And top hats! Always with the top hats, man!)