Rockets, Communists, and the Dewey Decimal System - S1-E2
Other mistake: As Young Sheldon is a prequel series to Big Bang Theory, this episode is at odds with episode 2-13 of Big Bang Theory, "The Friendship Algorithm," in which Sheldon is unfamiliar with books like "How to Make Friends and Influence People," which he reads in this episode of Young Sheldon, produced nine years later but taking place twenty years earlier.
A Solar Calculator, a Game Ball, and a Cheerleader's Bosom - S1-E5
Factual error: In this episode we see George throwing a ball against his bedroom wall. On the wall is a picture of Axl Rose wearing shorts in the pattern of the USA flag. This photo is from the Guns N' Roses appearance at Rock In Rio 2 festival in Jan 1991. The show is set in 1989. 2 years prior to the photo the poster is made from is taken.
A Solar Calculator, a Game Ball, and a Cheerleader's Bosom - S1-E5
Factual error: The commentary suggests that Sheldon had the correct solution to problem 1 and merely lost points on the quiz because he didn't show his work. In reality he did the first problem incorrectly. Taking the derivative of (x+2) ^2+ (y+1) ^2 = 13 with respect to x yields: 2* (x+2) +2* (y+1) * (dy/dx) = 0 which implies that: dy/dx = - (x+2) / (y+1) and at the point (0,2) this means that the slope dy/dx is actually equal to - (2/3), not 2/3. It is correct that when using the form y=mx+b at the point 0,2 reveals that 2=m*0+b, or that b=2. So the correct equation for the tangent line is y = - (2/3) x + 2, not y = (2/3) x + 2 as shown in the episode. (00:13:55)
Continuity mistake: When Sheldon is putting his mittens on at the table he his seen putting the first one on and the second one is on the table, the shot changes and the mitten is no longer on the table. He raises his hands and both hands have mittens on them. (00:01:55)
A Sneeze, Detention, and Sissy Spacek - S1-E13
Visible crew/equipment: When Sheldon is running away from Mary in the garage, the set lights are reflected in his helmet. (00:18:00)
Jiu-Jitsu, Bubble Wrap, and Yoo-Hoo - S1-E17
Plot hole: Near the start we see Sheldon using physics to try and take down Tam. This completely goes against all of Sheldon's phobias about touching people, especially socks. Even before this episode he has shown his displeasure at the thought of touching people. (00:05:00)
A Computer, a Plastic Pony, and a Case of Beer - S1-E12
Continuity mistake: When we see Sheldon in bed at the start he's either flat on his back or on his side depending on the shot. (00:03:45)
A Patch, a Modem, and a Zantac - S1-E6
Factual error: At the start of the episode when someone is talking at the podium, there's a a periodic table behind him on the wall. On the left of barium, 'Sc' for scandium is there instead of 'Cs' for cesium. (00:00:40)
Continuity mistake: When Sheldon and Missy are sitting at the table, Missy puts a paper in the basket in front of her. A couple of shots later when she says "sounds right" the paper has disappeared. In the next shot it reappears, in a different position than it was before. (00:06:20)
A Dog, a Squirrel, and a Fish Named Fish - S1-E20
Continuity mistake: When Pastor Jeff is talking about "Love Thy Neighbour," the Bible is open in his hands, apart from one shot where it closed. (00:13:20)
Summer Sausage, a Pocket Poncho, and Tony Danza - S1-E21
Continuity mistake: When Missy tries the Lobster for the 1st time, the way she holds her fork keeps changing between shots. (00:16:50)
Summer Sausage, a Pocket Poncho, and Tony Danza - S1-E21
Continuity mistake: When George Sr. is cracking the claw of the lobster, he goes from holding the cracker to holding a fork instantly. (00:16:38)
A Mother, a Child, and a Blue Man's Backside - S1-E18
Continuity mistake: When Sheldon is shown the M.I.T leaflet, the way it's displayed to him changes between shots. (00:09:20)
A Mother, a Child, and a Blue Man's Backside - S1-E18
Continuity mistake: When the guidance councillor holds up the leaflet for Caltec, where she holds it changes between front and rear camera angles. Note the distance from the top of the leaflet. (00:09:10)
A Computer, a Plastic Pony, and a Case of Beer - S1-E12
Continuity mistake: When Georgie meets Sheldon by the school lockers, he grabs his lunch bag from inside. From the opposite angle, he's taking it out again.
A Computer, a Plastic Pony, and a Case of Beer - S1-E12
Continuity mistake: When Mary lies in bed with Meemaw, the way Mary's right arm and hand lie on top of the left arm differs between shots. Check the way the hand covers the sleeve, for example.
A Computer, a Plastic Pony, and a Case of Beer - S1-E12
Continuity mistake: When Sheldon and Missy lie in bed together, her right hand is on top of her left. A shot later, it's the opposite way. (00:09:16)
A Computer, a Plastic Pony, and a Case of Beer - S1-E12
Continuity mistake: During the spaghetti meal scene, the way Missy holds her fork changes between the back and front shots, especially during the last shots.
A Computer, a Plastic Pony, and a Case of Beer - S1-E12
Continuity mistake: Sheldon pinches a loaf of bread, but a shot later he's pinching spaghetti. This changes back and forth a couple of times.
A Computer, a Plastic Pony, and a Case of Beer - S1-E12
Continuity mistake: When the family leaves the computer store, Missy's candy sucker swaps randomly between being in her mouth or not between one frame and the other.
Answer: Some people just have a dislike for someone that can't be explained. Could be as simple as the way he's dressed.