According to The News Manual, the three main reasons journalists use quotes are:
1.- By repeating or typing the exact words the source spoke during the interview the writer avoids misrepresenting their intended message.
2.- When a journalist writes exactly the phrase or words spoken he or she allows the readers to see the connection between the ideas expressed and the way they were specifically expressed.
3.- By quoting verbatim a source, a writer allows its readers to appreciate the speaker's particular speaking style and translate some of that 'liveliness' into the written page