Visible crew/equipment: While Leo and Piper are at the photography studio with their kids the Avatars appear, and in the shots facing the Avatars the red tape mark is visible on the floor, in front of Avatar Alpha. (00:01:10)
Someone to Witch Over Me - S7-E7
Visible crew/equipment: After Paige's guardian angel is snatched by Sarpedon, when Phoebe rushes out of the kitchen to find Paige lying on the floor, two long white tape marks are visible on the floor to Paige's left and right. (00:16:15)
Someone to Witch Over Me - S7-E7
Visible crew/equipment: When Kyle orders the helicopter to keep recording the survivor from the fire, Paige tells Phoebe that Kyle is really cool, then as Phoebe and Paige follow Kyle they pass the Celerity demon, and we can see the red T-mark at the demon's feet. (00:02:05)
Visible crew/equipment: After Leslie decides not to ring the manor's doorbell he turns around, and when he sees Phoebe as she walks up the steps, the reflection of crew members is visible on the car window behind Phoebe. Then as Phoebe and Les are talking, we also see the reflection of the boom mic on the window of the car in the driveway. (00:40:15)
Visible crew/equipment: After Phoebe fails to convince herself to push the elevator button she bumps into Les anyway, and when Phoebe tells him she's a "busy little bee" the camera angle changes, and we can see the pink and white T-marks on the floor. (00:10:00)
Charrrmed! - S7-E4
Visible crew/equipment: When Sheridan gets off the phone and tells Agent Brody that he checks out for now, in the next shot as Brody walks toward Sheridan we can see the T-mark on the floor where he had been standing. (00:24:40)
Something Wicca This Way Comes - S1-E1
Visible crew/equipment: When Jeremy wakes up in the freight elevator he rushes off to find Piper, and when it cuts to Piper and Prue in the living room, the reflection of the boom mic is visible on the glass of the framed photo, behind the couch. (00:36:20)
Something Wicca This Way Comes - S1-E1
Visible crew/equipment: When Piper and Phoebe are standing beside the car Piper kisses "Nancy Drew" goodbye, and Phoebe continues to tell her sister, "We're known as the Charmed Ones," then in the next overhead shot the reflection of the boom pole/mic is visible on the car's windshield, just as Piper drives off. (00:20:10)
I've Got You Under My Skin - S1-E2
Visible crew/equipment: When Prue walks into the manor and sees Brittany in the foyer, we can see the boom pole moving at the top of the doorway leading to the dining room. (00:35:20)
Witch Wars - S6-E21
Visible crew/equipment: While the demons are watching Witch Wars at the bar, when the show's host, Corr, is holding an athame he tells viewers the winner will be awarded a serious power boost, then just as Corr says, "Since the shapeshifter..," in the shot of the demon bar patrons, we see the T-mark (it is not part of the Witch Wars show) taped to the floor under the table. That T-mark is visible again in at least three following shots. (00:23:35)
Crimes and Witch-Demeanors - S6-E19
Visible crew/equipment: After The Tribunal reverse the decision about Darryl he reappears at his desk and he hugs Sheila, then as the camera pans around to reveal The Cleaner standing in the doorway, we can see the white tape mark on the floor behind his feet. (00:39:00)
The Courtship of Wyatt's Father - S6-E16
Continuity mistake: When Leo and the sisters are in the alley with darklighters, Phoebe falls from the roof and her high-heeled boots become flat shoes. (00:14:40)
Continuity mistake: When Chris tells Phoebe that searching for Jinny at the dig site may be a trap Chris is wearing a zipper hoodie, but in the next overhead shot just as Chris sees the hole containing bones Chris has on what looks like a leather jacket, and then it's back to the zip hoodie. This is odd, because it's not until later after Leo heals Chris, that we even see Chris in the leather jacket. (00:03:10)
Continuity mistake: When Phoebe is told that Jason asked not to be disturbed she decides to go in anyway, and right before she enters Jason's office the lace-up on the back of Phoebe's top is very loosely tied so we see a lot of skin, but when she's inside Jason's office the lace-up is tied quite tightly so only a bit of skin is seen. (00:11:40)
Valhalley of the Dolls (1) - S6-E1
Continuity mistake: When Paige and Phoebe throw the potion at Darryl to borrow his soul, Darryl's physical body lies face-up with nothing on him, but in the closeup the necklace with Darryl's badge is lying neatly atop his chest. (00:36:15)
Valhalley of the Dolls (1) - S6-E1
Revealing mistake: When the sisters summon the Trok demon Phoebe is wearing a bikini top, and as the demon blasts them all backwards into the wall, Phoebe is wearing something around her waist for the stunt. (00:07:20)
Visible crew/equipment: After Leo leaves Piper alone at Darryl's party in the park, when it cuts to Elise and Phoebe at P3, we can see the two T-marks on the floor behind them when they walk over to the counter. (00:12:35)
Necromancing the Stone - S5-E21
Visible crew/equipment: After Phoebe tells Jason that she'll go with him to Hong Kong in the morning, when it cuts to Piper and Paige looking out of the attic window, the reflection of a crew member is visible in the window behind the candles. (00:33:40)
Continuity mistake: Phoebe is making her coffee and pours cream in. The next scene it's almost overflowing and black.
Brain Drain - S4-E7
Revealing mistake: When the Chameleon Demon changes from a lamp to a demon he throws Piper and Phoebe with Telekinesis but Piper looks to the right before he motions the toss. (00:03:05)
Answer: That was a mistake in the series.
Also, the episode is called 'Babies First Demon' and this alone tells us that it's Wyatt's first time in the field (so to speak) and as the sisters say, they've done a good job of clearing up their own magical messes so far. Nobody really knows how advanced Wyatt's powers are, or will become. That's why the cleaners appear, to nip things in the bud. The Cleaners didn't want to chance that the sisters could clean Wyatt's magic up, just incase they couldn't. Therefore intervening themselves, just in case.