I’ve been a fan of his films, but as Anthony Lane nicely summarizes, there’s a deep flaw in Leigh’s work:

Devotees of Leigh, of whom there are legions, greet his careful scrutiny of faces as a compassionate mapping of deep trouble, as if he were Bergman. To my eyes, however, the litany of closeups is itself a troubling act of intrusion, touched with a cruelty that Bergman, for all his sobriety, seldom sought, and I gradually came to dread the next appearance of Mary, with her slurred, embarrassing miseries probed by the lens as if placed under a microscope.

Leigh can’t help exposing his characters in a way that betrays deep down I think, his lack of real sympathy for humanity; this is a streak you don’t see in current directors like Alexander Payne, who dwell in their stories on  people’s selfishness and cowardice, but never without reserving compassion for even the characters most morally flawed. (I think William Trevor and Alice Munro do this beautifully in short fiction.) And it’s very hard to achieve in film (Payne’s films are uneven, but still enjoy them).