Why did Li He's mother get angry when she learned that Li He had written many poems?

I'm just afraid that if he writes too many poems, he will be exhausted.

Every day at sunrise, I travel with gentlemen. I don't have any problems. Then I write poems, just like others think about the connection and limitation of the journey. Heng was a slave since he was a child, riding a donkey and carrying an old tattered kit. When he got anything, he put the book in his bag. When she got home at dusk, Mrs. Tai took the maid out of her bag and found many books inside. She said, "It's time for you to spit out your heart!"