6. Bale Hated The Costume (And Used That To His Advantage)
The big joke made about the Batman suit in the Burton films onwards was how it was impossible for the hero to turn his neck. No doubt playing a part in some of the nineties' more stifled performances, it was eventually refined in The Dark Knight, but not before Bale had suffered one go-around in the old style.
Hating it from the off, declaring "it's hot, dark and sweaty and it gives me a headache", much to the crews amusement, he kept going because he's a stubborn guy (and under contract), feeding the irritation into the character. It may be repurposed, but the irritation of being cooped up in one of superhero cinemas most restrictive costumes (the high levels of CGI mostly save Robert Downey Jr. from Iron Man) provided a great headspace for Bale to channel Batman's anger.