Continuity mistake: When Lucy's locked out on the penthouse balcony, Ethel places the broom handle through the small round finger hole of the scissors, with the large oval finger hole to the right of the round hole and the blades pointing out, then holds the scissors in place as she puts the broom over the balcony rail. When Lucy retrieves them from the broom, the scissors have flipped over. The blades are pointing out and the broom handle is still through the small round finger hole, but now the large oval hole is to the left of the round hole. (Impossible to do on its own. Try it). (00:19:05)
Continuity mistake: After Fred secures the chain lock to the front door, with the chain mounted onto the frame of the door, Fred then slides the chain into the door's slide-catch to show Lucy the "burglarproof chain." When Ethel opens the door the chain itself is ripped off the frame, leaving the chain (and the piece that was screwed to the frame) dangling from the slide-catch attached to the door, but in Ethel's closeup the chain is still mounted to the door's frame. (00:01:40)
Hollywood Anniversary - S4-E24
Continuity mistake: In season 2, "The Anniversary Present," Lucy has the 19th circled on the wall calendar, which is the date of their wedding anniversary, but in this episode when the license bureau in Greenwich, Connecticut sends Ricky a telegram with their wedding date, it's now on the 7th.
Continuity mistake: Ethel's full name in this episode is Ethel Mae Potter; however in a earlier episode, Fred calls her Ethel Louise, and in another episode she is called Ethel Roberta.
First Stop - S4-E14
Continuity mistake: In this episode, Fred and Ethel claim that the bed they are sleeping in is just like the one they have been sleeping on for years. It is double bed with a big sag in the middle. However in an earlier episode "Vacation from Marriage" they show Lucy and Ethel in the the Mertz's bedroom and they have twin beds.
Don Juan and the Starlets - S4-E18
Continuity mistake: After the maid sees Lucy sleeping on the couch and leaves, in the next shot the clock reads 10:00 and Lucy wakes up, but when Lucy checks the bedroom and walks back into the living room, the clock now reads 6:40. (00:16:25)
Continuity mistake: At the start, when the Pontiac convertible turns into the driveway of what should be the Beverly Palms Hotel, the sign with the real name of the hotel can be seen, which reads Beverly Carlton Hotel.
First Stop - S4-E14
Continuity mistake: When Ricky stops the car and backs up trying to locate Aunt Sally's, Lucy gets out of the car wearing a coat and a pantsuit underneath, but in the exterior shot she's wearing a skirt set when she walks over to the shed to read the sign. (00:03:50)
Continuity mistake: When Ethel asks her old friend Billy to take a group photo of her with Fred and the Ricardos, Ethel poses with everyone as Billy takes only one shot of them together, but when Lucy reads the newspaper article Ethel is posed differently in the cropped "group" picture. (00:12:15 - 00:16:35)
Answer: There is no reason. It's a just a silly plot device, typical of the era. Women characters were often portrayed as making uninformed assumptions or decisions.
raywest ★