Why do babies keep eating as if they are not full

Patient's question:

No

Doctor's answer:

It was a bit difficult to suck, I felt like she wanted to sleep, but when I put her down she cried and wanted to eat more. It was actually just that she got tired of sucking, but she wasn't full. I used a breast pump to express milk for her to eat, and it was much easier for her, and she could finally be full. It's just that the child doesn't have enough strength, she'll be better when she grows a bit older.