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

Explanation

Though Toto was pretty and clever, he was very mischievous. He brought a lot of damage to the house by breaking dishes, tearing clothes and curtains. He also scared the visitors by tearing holes in their dresses. Furthermore, he didn’t get along well with other animals in the house too. One day Toto crossed the limits by picking up a dish of pullao and running on a branch to eat it. When scolded he threw off the plate and broke it. That’s when grandfather decided he had had enough of Toto because he couldn’t bear the losses that he incurred because of Toto’s mischief.