Continuity mistake: When the guys arrive in Siberia, Flash knocks down a shovel which faces downwards. A shot later it's facing upwards.
Continuity mistake: When Zod stabs Kara, she collapses, her cape lying sideways. Watch before she lowers her leg, and you'll notice there's no cape underneath her. A shot later, the cape lies under her body, down along her legs.
Continuity mistake: After Bruce crashes against a table filled with boxes and food, he is covered in boxes. A shot later, when he tries to stand up, he is on top of the boxes and the way the food is scattered is completely different.
Continuity mistake: When Barry arrives at work and talks to his boss, the furniture and people around change all the time. Sometimes there's a white column on the left; others, there's a shelf next to it; yet others it vanishes and there's a box and a coat rack. Also, the guy on the right is sitting closer or further away randomly, despite the angle on Barry and his boss being always the same.
Continuity mistake: Right after Wonder Woman takes off, the people on the bridge vanish.
Continuity mistake: When Wonder Woman saves Batman and the other guy, there are skid marks on the right side of the road. When she takes off, they disappear.
Revealing mistake: When the Batcycle slams against the taupe BMW blocking the road, there is no driver inside, to allow for a safe stunt.
Continuity mistake: When Barry meets his mother at the supermarket, he wipes the tears off his right eye. Shot changes and he's wiping his left eye.
Continuity mistake: The taupe BMW is about to crash against a red car, but a shot later it's changed to a black/dark blue car. (00:04:43)
Revealing mistake: During the chase in Gotham, the armoured truck crashes against a jeep. The driver remains stiff as a board, unaffected by the violent impact or any laws of physics, revealing it's a dummy (or a CGI asset).
Continuity mistake: In Batman's lair, after Barry has been electrocuted, the blood on his nose and mouth suddenly vanishes.
Continuity mistake: Old Barry collapses next to Young Barry, and lies next to his waist. A shot later he lies next to his head.
Continuity mistake: At the lab, when Young Barry collapses, his head lies on a white tile and his hair is all messed. A shot later it lies on a coloured tile and it's not messed.
Revealing mistake: When the Barrys cross through the glass door, for a couple of shots, Young Barry's face is replaced with a non-realistic CGI face with features that don't match the face contour at all.
Continuity mistake: While Gary wakes up, the stuff on the table changes positions or disappears between shots.
Continuity mistake: The Flash eats half a burrito, but when it flies towards the knives, it's whole again.
Continuity mistake: When Gary shows his Eric Stoltz tattoo, his arm and hand are resting on his knee. From the opposite angle, they are not.
Continuity mistake: When Young Barry vanishes in the kitchen, the way his empty robe folds changes between shots. Also, the spoon falls on the robe but suddenly appears on the floor a shot later.
Continuity mistake: Young Barry forces Old Barry into eating broccoli, which he does in large bites. When Young retrieves the broccoli, it's uneaten.
Answer: Some possible reasons gleaned from the Internet: Filmmakers wanted a different vision of Supergirl to reflect a darker, grittier personality and to show her refugee-like experience. Her dark short hair symbolizes her harsher journey from her home world. Also, it gives her a more androgynous look, reflecting both her feminine and masculine traits. Those are all possible reasons, but adopting a radically different look for an established character generates more attention and interest in the film.
raywest ★