Pirkei Avot §avot_05_12: There are four types of disciples: Quick to comprehend, and quick to forget: ...

There are four types of disciples: Quick to comprehend, and quick to forget: his gain disappears in his loss; Slow to comprehend, and slow to forget: his loss disappears in his gain; Quick to comprehend, and slow to forget: he is a wise man; Slow to comprehend, and quick to forget, this is an evil portion.