Mair's essay is great but perhaps tl;dr. Here I just give two simple examples to illustrate the absurdity of trying to transliterate every individual character in Chinese - it may sometimes work but not always.
Each character can mean very many different things in many different contexts, and when paired together with other characters. The two characters in crisis = 危机 (wēi + jī) can BUT need not be transliterated as 危 (wēi) = "danger" and 机 (jī) = "opportunity".
As Mair notes, 机 (jī) = "opportunity" is not a very good transliteration in any case, but let's accept it for the sake of argument. It is not however the only possible transliteration.
Airplane = 飞机 (fēi + jī)
where the second character is the same as that for "crisis". The first character 飞 fēi is here (appropriately) transliterated as "fly(ing)". If we insist on transliterating the second character 机 (jī) in this context again as "opportunity", then an "airplane" = "flying" + "opportunity". Which is absurd.
In this context, 机 (jī) is more appropriately transliterated as "mechanism" or "machine", so that "airplane" = "flying" + "machine".
Organic = 有机 (yǒu + jī)
where again the second character is the same as that for "crisis". The first character 有 (yǒu) can be transliterated as "there is". And so again if we insist on transliterating the second character 机 (jī) in this context again as "opportunity", then "organic" = "there is" + "an opportunity". Which is absurd (except to organic food proponents seeking Chinese nuggets of wisdom).
In this context, 机 (jī) is difficult to transliterate - but if one insists on doing so, perhaps "life" or "substances capable of life" is the best. The word on its own does not quite have a sensible transliteration. So 有机 = "there is" + "life" = Organic.