Continuity mistake: When Dorian puts on the mask for the first time, right before all the smoke starts reducing, pay close attention to his goons. Some of them change position. (Clearly those were two takes pasted together, one with Dorian without the mask, and one with.) (01:04:25)
Continuity mistake: When The Mask first visits the Coco Bongo and dances wildly with Tina, they perform a series of impressive manouvers and The Mask then dips Tina and holds her in that position. At this moment, Tina is revealed to be a stunt double, not Cameron Diaz, just before the camera zooms into a close up of Jim Carrey.
Continuity mistake: When Dorian, as The Mask, breaks down the doors of the Coco Bongo, you see the door topple onto the doorman on the left. When the camera cuts back, he is on top of the door. (01:17:25)
Continuity mistake: When Dorian's boss shoots him in the stomach it switches from the boss to Dorian several times. Each time Dorian's buttons change colours from black buttons to white buttons to no buttons. (01:18:25)
Continuity mistake: When Tina goes to the jail and meet Stanley they almost kiss for the first time. She is wearing bright red lipstick. A few minutes later she is running down an alley outside of the prison from Dorian. She is wearing soft pink lipstick. (01:09:00)
Continuity mistake: While in Mrs. Peenmans' hall, just before she shoots him, his hands switch places on the mallet. In the first shot, his left hand is on the bottom, right hand is on the top. In the other two shots, it is vice-versa. (00:18:15)
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Continuity mistake: When The Mask is making balloon animals, one gang member switches position between shots, shifting to the side of the gang leader to behind him. (00:21:26)
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Continuity mistake: When Stanley is beating up Dorian, Dorian's head is either lying against the ground or raised, depending on the shot. (01:27:49)
Answer: I think that the reason he is so grumpy and cynical is because he has been a police detective for SO long that all the crime he's investigated has made him jaded. I think that it is the same with any regular human being, one can only do the same thing day in and day out for so long before it affects you, negatively. Plus his home life may have been a contributing factor also. As to why he didn't thank Stanley, maybe he just didn't like him.
Alan Keddie