Do not overquote from sources, that is have too many direct quotations or excerpts that are too long. This problem has existed for years, and there are several issues to beware of:
Even though typical copyright laws allow a limited amount of quoting from sources, with proper attribution notes, the total amount of text should be kept to a minimum. The contemporary term "soundbite" is a similar restriction, as a short quotation, rather than a lengthy blurb that fills the space with long-winded excerpts from a source. The Chicago Manual of Style (17th ed 2017) section 4.86 states: [1]
As a general rule, one should never quote more than a few contiguous paragraphs of prose or lines of poetry at a time or let the quotations, even if scattered, begin to overshadow the quoter's own material....Proportion is more important than the absolute length of a quotation: quoting five hundred words from an essay of five thousand is likely to be riskier than quoting that amount from a work of fifty thousand. But an even smaller percentage can be an infringement if it constitutes the heart of the work being quoted.
In particular, the U.S. fair-use restriction for copyrighted song lyrics has stated a limit of quoting, at most, 10% of the total lyrics, or less than a "performable unit" of the work. In many cases, it is not necessary to directly quote whole lines from a song, but rather, just mention some key phrases, without attempting to "sing the song" in an article. However, when a song is no longer under copyright, then quoting some lyrics could help explain the nature of the song to readers.
The lead section of an article should be limited to a summary about the topic, rather than a collection of long quotations. The guideline WP:LEAD explains the suggested style of the lead section, as being just an overview as introductory lead paragraphs. However, special care should be taken to avoid long direct quotes in the lead, from specific sources. Instead, write concise, plain text which could be adjusted, or extended, also by other editors, to better reflect current ideas about the article's topic. A major problem with quotes in the lead is the concern about giving WP:UNDUE weight to one or a few sources within the limited space of the lead section. The general goal is to allow the lead to contain free-form text which can be altered, easily, to reflect both old and new issues, which might not be covered by quoting from an older source which lacks the new perspectives.
Quotations should not substitute for exposition in Wikipedia's own voice. They are useful for capturing the original author's tone or attitude, but shouldn't be used instead of a clear editorial summary of what they say.
