Mediocre people find it hard to accomplish great things.
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Literary, slightly negative. Often appears in the reduplicated form 庸庸碌碌 (yongyong lulu) for emphasis, or in the fixed phrase 庸碌无能 (yonglu wuneng, 'mediocre and incapable'). Stronger than 普通 (ordinary).
memory
庸 = mediocre/ordinary; 碌 = busy with trifles. Together they paint someone who's busy but with nothing meaningful - the Chinese version of 'spinning your wheels.'