Hyphens remain a mystery in many parts of speech, but they can play a pivotal role in changing the structure of a sentence. For instance, consider the following phrase:

John is a small business owner.

To the lazy eye, this sentence will read as though John is the owner of a small business. In reality, it describes John as a business owner who is small. This can be remedied with the addition of a hyphen:

John is a small-business owner.

The difference here is that "small" applies only to the business, not the owner. With the addition of a hyphen, "small" is directly connected with "business" such that "small-business" becomes a single adjective. There is no longer any confusion as to whether it is the business or the owner that is small. The helpful hyphen eliminates confusion. (Thank you, helpful hyphen!)

Let's try another example:

While Ace and Tracy were having the immaculate conception debate, I read my European history textbook.

The lazy eye would interpret this sentence to say that Ace and Tracy were debating about immaculate conception while the narrator read her book on European history. Unfortunately, without hyphens, Ace and Tracy are actually having an immaculate debate about conception while the narrator is reading her history textbook—which was manufactured in Europe. If we wanted this sentence to say the former, we could add hyphens:

While Ace and Tracy were having the immaculate-conception debate, I read my European-history textbook.

Or, we could simply rearrange the sentence (which, in this case, would seem more intuitive):

While Ace and Tracy were debating about immaculate conception, I read my textbook on European history.

We can rearrange the sentence in the case of small-business-owner John as well:

John owns a small business.

By rearranging the sentence, you avoid the need for hyphens altogether. However, there will be some cases where the hyphenated version will be more desirable.

As with most rules of English grammar, however, it is not that easy. There are exceptions to the hyphenation rules. For instance:
-Names need not be hyphenated, e.g. the Oxford University library.
-Phrases which involve a verb ending in ‘ly' need not be hyphenated; e.g. an abruptly ended seminar. The seminar cannot be "abruptly," so it can't be mistaken that "abruptly" describes the seminar.

So what about this phrase:

Jay thought the violins were well orchestrated.

This is a phrase that is commonly hyphenated, but "well" and "orchestrated" do not need to be hyphenated. There is no confusion about what "well" applies to; there's no way that the violins could be "well" the way the sentence is phrased. Since there is no opportunity for confusion, no hyphen is needed.

Here are some rules of thumb with regard to hyphenation:

-If you are qualifying a qualifier ("business" qualifies "owner;" "small" qualifies "business"), be sure to use hyphens to indicate the correlations between the qualifiers and the noun being qualified.
-Read the sentence over. If there's room for confusion, rearrange the sentence until there isn't.

Sources used: Chicago Manual of Style, 15th ed. Sections 5.92 and 5.93