Stupidity: Patrick told Dwayne to get Cisneros to kill Zara, apparently because he believed Cisneros could get the job done. Cisneros went into Zara's house with his gun ready to shoot, but not before pinpointing Zara's location. He saw the refrigerator door open yet entered the room without looking left and right (behind the door); Zara was able to disarm him. Zara was also able to escape Cisneros' repeated crazy swings at her with a samurai sword. Zara fatally "sliced" his neck with a pizza cutter. (00:21:44 - 00:23:07)
Stupidity: After the Sheriff was shot in the neck but was able to run into the woods, he hid behind a wide tree trunk. He shot at the Virtuoso but missed. Instead of staying behind the wide tree trunk and shooting again as the Virtuoso advanced toward him, he flees from tree to tree where the trunks are not as wide, giving him less protection and more of a disadvantage. Eventually, he is killed by the Virtuoso. (01:21:48 - 01:22:26)
Stupidity: Two things: 1. I find it inconceivable that there is only one Carbon Dioxide Removal Assembly (CDMA) and no spares for a two-year mission. 2. The crew has 20 days to fix an oxygen problem. The commander decides on a 10-day window. 5 days into that window they try to load oxygen from the Kingfisher spacecraft. One is lost into space. Zoe decides to go and fill the other one in the midst of a solar storm that will only last hours. Why take that chance? A few hours wait is still quite possible.
Stupidity: Patrizia Reggiani is no rocket scientist in this movie, but it's quite bizarre that calling the fortune-teller she sees on TV, with her name written in giant letters in two different spots on screen, she asks her "What's your name?" It makes sense for the international audience who may not recognize the word "Pina" as a name, but an Italian wouldn't have any doubt. (00:41:05)
Stupidity: Jimmy parked his truck on the side of the road with woods running parallel and starting about 10' away. Jimmy moved to the passenger side so the Sheriff could sit in the driver's seat (for no apparent reason). After Jimmy threw the "white powder" into the Sheriff's face, he quickly got out of the truck and ran straight ahead on the road instead of ducking into the nearby woods. The Sheriff had a clear and easy shot to hit and kill Jimmy. Also, Jimmy should have been much further away. (00:11:51 - 00:12:21)