Charrrmed! - S7-E4
Continuity mistake: When Piper watches Leo sleeping with Wyatt and Chris, the book on Leo's chest disappears and then reappears. (00:38:45 - 00:39:15)
Charrrmed! - S7-E4
Continuity mistake: When Black Jack Cutting's parrot delivers the invitation to Piper and Phoebe, it drops the invitation on the window sill. When Leo goes to pick the letter up, it moves closer to him than it was before (in particular, watch it relative to the parrot's left foot). (00:29:40)
Someone to Witch Over Me - S7-E7
Continuity mistake: When Paige talks to agent Brody at his apartment, her hair moves from covering her shirt straps to not, then covering them again. (00:09:45)
Continuity mistake: When Paige is complaining to Leo about not having time to take on a charge as a Whitelighter, she rests her head in both of her hands on the kitchen table. In the next shot, her head is only resting on her right hand. (00:00:30)
Continuity mistake: When Phoebe talks to Leslie about him leaving, her arms change between shots from hanging by her sides to her hands clasped together in front of her. (00:11:50)
Little Box of Horrors - S7-E18
Continuity mistake: When Paige complains about the ringing in her ear, she's rubbing her temple with her right hand and holding a coffee mug with her left. In the next shot, which is cut too fast for her to have moved, the hand on her temple has jumped to holding the coffee mug. The mug has also jumped to in front of her mouth. (00:01:45)
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.