Pick apart

From A Wheel of Time Wiki

Weaves of the One Power can be picked apart by the channeler holding them, and once a thread has been removed it can not be put back. After the first thread has been removed from a weave the remaining threads start to become slippery and hard to grasp. Additionally the threads have a tendency to snap together into random weaves, with potentially disastrous results. The more complex a weave the more threads it has, and thus the longer it takes to pick apart, and the slipperier the threads get while you work, making complex weave much harder to unpick then simple weaves. The White Tower teaches it's Novices never to try to un-pick a weave, and Aes Sedai believed it to be impossible to do so successfully, indeed even the Forsaken didn't believe it was possible until Aviendha picked apart a Gateway to prevent anyone using the residue of the weave to follow herself, Elayne, Nynaeve, and the Kin to the kin's farm where they planned to use the Bowl of the Winds to fix the weather.

Aiel Wise Ones teach their apprentices to pick apart weaves by trying it on a simple knot of air, the usual result is a loud boom and it takes many tries before they can do it successfully. Failing to pick apart a weave is known to burn out not just the channeler trying it, but those in the area as well.