这句是省略句，省略了一个Being 还原Being good is must;Being successful,however,is plus.可以看出Being good is must;however,being successful is plus.
做好是必须的，做成功则是额外的。意译：
先做好自己，再追求成功。进一步：
成功先成人。...
原话是：Being good is must; being successful, however, is plus.Being good is must; (being此处省略) successful（是形容词，不是副词。副词是successfully）, however, is plus.做好自己是必须的，成功是附加的。也就是：做好了...
