In "The Lumber Room" by Saki, how do the Aunt's efforts to punish Nicholas boomerang on her?

In “The Lumber Room” by Saki, the aunt’s plan to punish Nicholas goes awry in a number of ways.  After Nicholas finds himself “in disgrace” for putting a frog in his breakfast, the aunt arranges a day at the beach for the other children. She expects Nicholas to be distraught, but instead he informs her that the beach excursion will be a disaster because she did not listen to the complaints of the children.
While the others are gone, she forbids Nicholas from entering the gooseberry garden, and she spends her day ensuring that he stays away from the natural delights found within the garden walls. However, Nicholas has other plans for his day. He tricks the aunt into thinking he secretly entered the garden when, in reality, he is in the house enjoying an adventure in the lumber room.
The aunt is frantically searching for Nicholas within the garden walls when she falls into the water tank, where she is trapped. As she calls for help, Nicholas enters the garden and subjects her to a line of questioning, which tricks her into incriminating herself. Nicholas leaves her in the garden tank and returns to the house. A servant rescues her, the others return from their disastrous adventure, and the aunt pouts through an eerily quiet family meal at the end of the day.
The aunt’s plans to punish Nicholas boomerang because she wastes her day policing him, while he enjoys his adventure in the lumber room. In addition, she falls into the water tank, and the other children have a terrible day at the beach. She suffers punishment while Nicholas outsmarts her.