Why does the above phrase (马马虎虎- lit. Horse horse tiger tiger） mean so-so or moderate?
Curious as to how animals can represent expressions
詞源 出自滿語 lalahuhu。 《滿語雜識》並無此詞，但愛新覺羅‧瀛生在《滿語和漢語中的互相影響》一文曾提及有 lahu 一詞，滿語本義為「打獵沒本領」，北京等地方言謂「行事不利」、「抓不緊」為 lahu。lahu 在北京話就是「喇忽」（而不是「馬虎」），「喇忽」是粗心、疏忽、漫不經心的意思。同樣，王惠樵的《河東方言語詞輯考》中亦謂「河東俗謂人凡事不經意，大大列列為『喇忽』」，而其疊詞亦可引申為對什麼都不在意，如老舍《全家福》第一幕：「林三嫂三十好幾了，還像個孩子，喇喇忽忽的。」，胡零《識時務者》：「沒什麼，因為我這個人喇喇忽忽的，有很多不好的地方」。後轉為「馬馬虎虎」
「馬馬虎虎」is sound-alike version of「喇喇忽忽」
It originated from 「喇忽」/「喇喇忽忽」in Beijing area dialect that meant "careless; negligent; casual"
Eventually the reading of 「喇忽」/「喇喇忽忽」 evolved into「馬虎」/ 「馬馬虎虎」(easier to read and remember perhaps?)
The Manchu language expression 'lahu / lala huhu' which means "no skill in hunting" was imported from this Beijing dialect phrase.
The Cantonese term 麻麻地 /maa4 maa4*2 dei6*2/ (so-so; not too good, not too bad) was in term, evolved from 馬馬虎虎
From a playful point of view, there was a story going that a painter is so careless that he could draw an animal which looks either like a tiger or a horse, so when asked if it is a tiger or a horse, he gave his answer as 马马虎虎, which means you can make your own judgment, but I woon't give you the exact answer. Chinese worldly wisdom can be seen from this.
马虎 and 马马虎虎 means careless. well, 马马虎虎 has another meaning. It comes like "you have done something not very well" eg, how was your test result from the examination? if you answer 马马虎虎, you are trying to express it's not very good (but not that bad, could be at least acceptable) . I would rank it a bit lower than ok or just ok (not above ok).