Why should they? Take logos for example. Why should it always be translated with the English gloss of word? The word word is a primary meaning,but not a so-called literal meaning. It also would not make sense in a number of places. Even Young's doesn't "translate" it as word each and every time.
Lets take the word "logos" and consider how it is translated:
It appears in the NT about 330 times.
Sometimes the meaning is Jesus Christ, i.e. the Word with a capital W.
But lets look at Matthew 5:32. The KJV translates logos as "cause". The ESV translates it as "ground," i.e. basis. The HCSB translates it as "case." The NKJV translates it as "reason." The idea is that except on account of sexual immorality, divorce is sinful. Now logos is translated 8 times in the KJV as account, and so there is no reason not to translate logos as account here.
Next, Matthew 5:37 translates logos as "say" "word" "communication" or "statement." Why not stick with the other 200 plus times it is translated word?
Next, Matthew 21:24 in the KJV translates logos as "thing." Most other versions translate it as "question." But again the underlying reasoning, or basis or principle is in view. Thus maxim fits nicely.
Finally, for this is enough for one post, Matthew 22:15 translates logos as "talk" but "speech" would work just fine.
Bottom line, there is no good reason to translate logos by using more than 30 different English words, when a concerted effort could probably reduce that number to 6 or 7. This would also mitigate overlap where the same English word is used to translate different Greek words, obliterating the distinction made in the underlying language.