The Un-Hateable Norman Bates
Think, for a moment, about how the famous shower murder really unfolds. Yes, we never saw a knife blade puncture naked flesh(though we saw such a blade TOUCH against the naked belly) and yes, the blood was fairly minimal.
But the BRUTALITY of the murder was overpowering. Stephen King has written that "it seems to go on forever" and the stance of the Murderous Mrs. Bates is merciless...the "arc" of the scene is how Marion tries to fight back for a little while, receives one or two first disabling stabs, and then is anhilated in a furious frenzy of stab after stab after stab.
Its mean, and its painful, and its cruel and yet...
...the man who does it(Norman Bates) somehow stays on our good side for the duration of the movie right up until, in the final scene in the cell, the monster within finally emerges on the now-hideously grinning countenance of the killer Norman truly is.
The negligible sequels rather idiotically played off of the "sympathetic" qualities of Anthony Perkins as Norman Bates. His boyish looks(even in middle-age in the sequels.) His nervous, stammering, shy manner. His little jokes. Psychos II and III featured a "new" deputy sheriff who kept threatening people to "leave poor Norman alone, he's suffered enough" and young women are attracted to Norman in varying degrees: Meg Tilly in II likes him; Diana Scarwid in III loves him, and some unknown actress in IV MARRIES him(even after the shower murder and other horrible crimes.)
Now, compare, sweet , nice and likeable Norman in Psycho to three other psycho killers:
Bob Rusk in Hitchcock's own Frenzy. Bob puts on a cheery front in his "day job" life(he's as likeable as Norman in that regard) but behind closed doors with a woman(one of many) he rapes and strangles, Bob becomes so, SO hateable. He menaces his female victim, roughs her up, throws her around, rapes her, chokes her a little bit in anger(violent enough) before strangling her as full-blown killer. You just HATE Bob Rusk(he's a sadist who picks on women, and as a man, you just want to strangle HIM), and his "cheery side" never fools us again after that scene.
Scorpio in Dirty Harry. We never really get to know Scorpio's roots or life. Probably horrible. But what we get now is a cackling, leering psychopath who likes to taunt the police by burying a teenage girl alive and sending her pulled tooth as proof that he has her; in other scenes, Scorpio simply flat out kills an African-American boy, a beautiful young swimmer; a cop. He hijacks a school bus full of young children and threatens to kill them AND their parents. Boy is Scorpio hateable. And coming along in R-rated 1971, he set the needle up to 11 in monstrous villainy. Boy was it great to see him get stabbed in the thigh early on and shot to death at the end.
Robert Shaw's subway car hijacker in The Taking of Pelham One. Nothing like a hostage taker to set the blood boiling in hate. Shaw and three accomplices take over a subway car, stop it in a tunnel and threaten to kill "one person a minute" if money isn't delivered. Like Scorpio with his buried-alive teenage girl, the "ultimate in hateability" is the villain who holds the good guys at bay with hostages. And when Shaw indeed coldly kills his first hostage...the rage peaks.
I suppose one reason that Perkins' Norman is NOT hateable is we never see him being a villain. He holds no one hostage, threatens no one, beats no one, rapes no one, and -- for the duration of Psycho -- does not seem to be the killer at all(though he is a distressingly compliant and unconcerned accomplice to this mother's killings and clean-ups.)
No, for most of Psycho we reserve our hate -- and our FEAR -- for that abnormally strong and completely merciless "old lady" and even there, I would say that she is so terrifying as a "killing machine"(first with Marion, but later with Arbogast and even more savagery) that we don't have TIME to hate her.
Hitchcock pulled something off that was truly amazing with Norman Bates. By centering the movie around such a sweet young man("Tony, you ARE this movie," Hitchcock told Perkins as they began their work), Hitch had himself a sympathetic character around which to build the movie, and then -- he never really showed NORMAN killing anyone.
Its another way in which the "twist ending" of Psycho demonstrated how you can manipulate your audience into ANYTHING -- in this case, sympathizing with a man who stabbed an innocent naked woman to death for no "logical" reason at all(though the SEXUAL motivation is clear as day, in the end.)
Anthony Perkins said he got a lot of fan mail for his work as Norman -- and fan mail FOR Norman. Nobody seemed to mention the murders at all - -they identified with the loneliness of the character, his quiet ways, and how the world knocks people like Norman around with callous uncaring.