The Economist has a post explaining why it does not use bylines.
It writes, “Part of the answer is that The Economist is maintaining a historical tradition that other publications have abandoned. Leaders are often unsigned in newspapers, but everywhere else there has been rampant byline inflation (to the extent that some papers run picture bylines on ordinary news stories). Historically, many publications printed articles without bylines or under pseudonyms—a subject worthy of a forthcoming explainer of its own — to give individual writers the freedom to assume different voices and to enable early newspapers to give the impression that their editorial teams were larger than they really were. The first few issues of The Economist were, in fact, written almost entirely by James Wilson, the founding editor, though he wrote in the first-person plural.
“But having started off as a way for one person to give the impression of being many, anonymity has since come to serve the opposite function at The Economist: it allows many writers to speak with a collective voice. Leaders are discussed and debated each week in meetings that are open to all members of the editorial staff. Journalists often co-operate on articles. And some articles are heavily edited. Accordingly, articles are often the work of The Economist‘s hive mind, rather than of a single author. The main reason for anonymity, however, is a belief that what is written is more important than who writes it. In the words of Geoffrey Crowther, our editor from 1938 to 1956, anonymity keeps the editor ‘not the master but the servant of something far greater than himself…it gives to the paper an astonishing momentum of thought and principle.’ The notable exception to The Economist’s no-byline rule, at least in the weekly issue, is special reports, the collections of articles on a single topic that appear in the newspaper every month or so. These are almost always written by a single author whose name appears once, in the rubric of the opening article. By tradition, retiring editors write a valedictory editorial which is also signed. But print articles are otherwise anonymous.
“Different rules apply on our website, however. A few years ago we decided to start using initials as bylines on our blog posts, to avoid confusion on our multi-author blogs (such as Democracy in America, which covers American politics). Our journalists can and do disagree with each other on our blogs, so we use initials to enable readers to distinguish between different writers.”
Read more here.