Revealing mistake: At Freddie Filmore's radio show, when Lucy steps out from behind the curtain, a bit of the kitchen from the Ricardo apartment is visible behind Lucy; it's the cabinet area with plates and canisters, beside the refrigerator. (00:06:15 - 00:19:40)
The Séance - S1-E7
Continuity mistake: After Lucy tells Mr. Merriweather that he's invited to the seance, when it cuts to Lucy unfolding the card table legs, note the couch behind her with one normal seat cushion on the left, but in the next wideshot there's an additional shorter cushion under the normal cushion. The small towel also repositions itself neatly on the couch. (00:11:55)
Revealing mistake: At the Brown Derby, when Lucy bumps into the waiter causing him to trip and spill the tray all over William Holden, we can see that the waiter's hand is taped to the bottom of the tray for the stunt to be done efficiently. (00:15:15)
Lucy Gets Ricky on the Radio - S1-E32
Visible crew/equipment: At the start, after Fred and Ethel walk in, when Lucy and Ethel walk away from the kitchen shutters carrying things, the stage microphone and stand can be seen at the right side of the screen. (Later in the episode, when Lucy and Ricky appear in the quiz segment an identical microphone is on stage with them). (00:00:35)
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)
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)
Lucy's Showbiz Swan Song - S2-E17
Other mistake: While Lucy and Ethel are auditioning their act for Ricky at the club, just as Lucy spins around watch her hands as she very quickly pulls on the string at her waist, which causes her pantaloons to loosen and fall to the floor. (00:12:05)
Visible crew/equipment: When the chicks are running loose in the living room, and Lucy, Little Ricky, Fred and Ethel are trying to corral them, you can see the chicken wire and braces set up to keep the chickens on the set. (00:20:20)
Ricky and Fred Are TV Fans - S2-E31
Visible crew/equipment: When Lucy decides to use the scissors to cut the TV wire on the roof, she and Ethel walk out of the kitchen, and at the start of the next shot we can see the end of the set wall and black cables on the floor, at the right side of the screen.
Lucy Wants New Furniture - S2-E28
Revealing mistake: When Ricky startles Lucy in the kitchen just as she's getting the salt, she climbs up through the kitchen/living room window, and in the shot from the living room when she and Ricky step down onto the chair, we can see the four long metal brackets which bolt the chair to the floor for safety. (00:13:15)
Lucy Thinks Ricky is Trying to Murder Her - S1-E1
Visible crew/equipment: When Ricky and Lucy are dancing in the living room, the camera swings too far to the left, and the edge of the set wall and the adjoining bedroom set can be seen briefly.
Visible crew/equipment: When Ricky is with John Wayne in his dressing room at the studio, getting yet another set of footprints on the block of cement, three T-marks are visible on the floor. One of those T-marks can be seen closeup when Wayne is lying on the table for his rubdown. (00:18:10)
First Stop - S4-E14
Visible crew/equipment: While Lucy and Ricky are lying in the sagging mattress "canoe", when the train passes and their bed rolls towards the bunk bed, the end of the set wall is visible at the right side of the screen. (00:17:30)
Visible crew/equipment: When Ethel's on the stoop in front of the building waiting for Lucy and Ricky, right before Ethel asks Ricky about Lucy's driving lesson, just as Ricky drives up we can see cables moving in front of the new Pontiac pulling the car. Then, when Ethel crashes the new Pontiac into the old car, the jiggling cables are again in front of the new car. Lastly, when Lucy finally starts the old car's engine, now there's a moving cable in front of the old car as well. (00:09:50)
Never Do Business With Friends - S2-E32
Other mistake: When Lucy and Ethel are on the back porch fighting about the washing machine and also when Mrs. Trumble walks out, Lucy's back door is open and we can see the shutters between the kitchen and living room, with the kitchen counter/sink underneath, but the sink's faucet which should be seen has vanished. (00:14:45)
Visible crew/equipment: During the scenes at the small diner when it's open for business, such as when Marco walks in, there are two small chalk T-marks on the floor in the area near the door. The T-marks are also visible when Ethel and Fred walk back inside. (00:12:35)
Visible crew/equipment: While Ricky and Fred are trying to clean up the volcanic rice eruption, when Ricky slips on the floor the second time the front edge of the raised kitchen set's platform can be seen. (00:19:15)
Bonus Bucks - S3-E20
Visible crew/equipment: After Ricky sneaks the dollar bill into Lucy's purse he sees her stirring in bed, and when Ricky ducks down to hide from Lucy, the two curved chalk actor's marks are visible on the carpet. (00:07:15)
Visible crew/equipment: After Lucy and Mr. Beecher sign the lease, just as they all start heading toward the door, the taped T-mark is visible at the bottom of the screen at the edge of the carpet (presumably for the second camera dolly offscreen at the left). Then as Mrs. Hammond walks out, a bit of overhead set equipment can be seen at the top right side of the screen. (00:12:45)
Continuity mistake: While tired Lucy is trying to open the card table's legs, she lays her head down then falls asleep, and when it cuts to Ethel and Fred walking in on our sleeping Lucy, there's writing on the table's underside which wasn't in the previous shot. (By the markings on the table it also looks as if the table has been turned on its adjacent side). (00:06:10)
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 ★