Why does the author say, “Toto was not the sort of pet we could keep for long”?

The author said that Toto was not the sort of pet they could keep for long because he was very mischievous and kept destroying things at home. He would tear things to pieces. He would make every effort to tear a hole in the narrator’s aunt’s dresses. On a particular instance, the narrator and his family saw Toto on the dining table stuffing itself with rice. In order to spite the grandmother, he threw the rice dish down from the tree and chattered with delight when it broke into pieces. The narrator and his grandfather realized that they were not too well-to-do and could not afford the loss of household items on a frequent basis. It is for this reason that grandfather sold Toto back to the tonga-driver that too only for three rupees.