Why does the grandfather tell Ishaan about running after other people's kites?

On the morning of Makar Sankranti, the roofs of the old city were crowded with people, and the sky above them was full of kites. Ishaan, who was eleven, had spent a week making his: a red kite with a long blue tail, and a reel of string he had coated with rice paste and powdered glass until it was sharp.

For an hour his kite danced higher than any other on the street. Then a green kite from the next roof crossed his line. Ishaan pulled; the other boy pulled harder. There was a soft snap, and the red kite floated free, drifting slowly away over the rooftops.

Ishaan did not cry, though his throat felt tight. Below, a crowd of small children was already running through the lanes after the falling kite, shouting.

His grandfather, who had watched from a charpai in the corner, called him over. "Do you know what I liked best about Sankranti when I was a boy?" he asked. "Not my own kites. I lost most of them. I liked running after other people's."

He gave Ishaan two rupees. "Go," he said. "There will be another one falling soon."

Ishaan ran down the stairs. An hour later he came back with a torn yellow kite, a scraped knee and a grin as wide as the sky. He had not won anything, but he had caught something, and somehow that felt better.