Wikipedia's external-links guideline gives most infoboxes exactly one line for a subject's official website: a single field, filled in once, that renders automatically everywhere the infobox appears on the page. A second copy of that same address, added further down in a section called External links, duplicates it — not against an editor's taste, but against the guideline's own wording.
A mid-size industrial-parts manufacturer had already filled that field when its marketing department asked for four more additions: the same homepage repeated under External links, a LinkedIn company page, an X account, and a PDF press kit hosted on the company's own server. An editor reverted all four within the hour and cited WP:ELNO in the edit summary. Three of the four fail on sight. WP:ELPOINTS treats a second link to an already-linked official site as redundant, and WP:ELNO excludes social-media profiles by default, with a narrow exception for subjects notable for the platform itself. The press kit fared no better — a page written by the company, about the company, hosted on the company's own domain, gives a reader nothing that a proper citation wouldn't already supply.
Citations and external links do different jobs, and mixing them up is the most common mistake in a link request. A citation supports one specific sentence and has to clear the bar that sentence sets: independent, reliable, checkable. An external link supports nothing in particular — it points toward a resource too large, too detailed, or too tightly copyrighted to fold into the article itself: a complete discography, a searchable grant register, a government filing database. Measured against that job, "add our link" usually turns out to mean "add a second homepage," and the infobox already has one.
Wikipedia is not a mirror or a repository of links, images, or media files.
A regional history museum's page shows the other side of the same test. Its infobox carries the homepage. Its External links section carries one more line: a link to the museum's online collections database, a searchable catalogue of roughly eleven thousand objects no article could reasonably describe in prose. Three separate clean-up passes by new-page patrollers have left that link standing, because it clears WP:ELYES on its own merits — it offers something the article's text and its citations genuinely cannot, and it isn't selling anything.
The question worth asking before a link request reaches an editor is simple: does the page behind that address do something the infobox and the citations don't already do? Checking the infobox first settles most of these requests before anyone has to revert them; the ones that remain tend to fail the same test the manufacturer's press kit did, and resubmitting them doesn't change the answer.
