Why do URI-shorteners suck ass?

URI (it's URI, not URL!) shorteners shouldn't exist to begin with. All links belong to the site that creates them. Putting links to your site in the hands of a third party equals putting your site's traffic at risk.

Every shortened URI is a sign of a design flaw

Short and meaningful URIs are great, especially for use with social media. Every site should make use of them. Unfortunately, many site's can't, because lazy or utterly clueless developers made sure that each and every URI is long, ugly, and totally meaningless to the visitor. Using short URIs to mask the crappy originals might sound sensible then. Actually, shortening URIs adds a flaw to a flaw giving a bug.

Every piece of content must be reachable via one and only one URI. Every URI must point to one and only one piece of content.

Creating multiple URIs serving the same piece of content adds noise and confuses search engines, user agents (browsers), bookmark managers, and humans as well. At how many phone numbers can I reach your cell phone? One. And that's enough.

There's nothing to say against fixing a crappy site architecture with an integrated URI shortener (creating short URIs that serve the content without redirects). Using an external URI shortener, even running on a domain belonging to the site, increases the noise and obfuscates the signal.

Every URI should serve its content fast and without detours.

It's should because in rare cases redirects are unavoidable, but please read it as must. Redirects aren't your friend. With every redirect you slow down your page loading time, and each redirect is a point of failure.

Murphy's law as well as common sense tell you that when there's a point of failure, it will raise a failure sooner or later, or even sporadically. In other words, redirects cost you human traffic. Massive redirects will produce a massive loss of traffic.

Not to speak of the pretty complex task managing your redirects when you've created redirect chains. Trust me, once you go that route you'll end up with multiple redirects in a row, some of them performing infinite loops.

Go fix your site, don't play with URI shorteners.

If you need to shorten 3rd party URIs before someone else does it, then roll your own URI shortener. Just don't feed it with your very own links. Make your URIs short instead to prevent them from shortening. Design your URIs.

Apropos someone else:

A billion flies can't fail: eat more shit.

When Twitter made URI shortening popular, they've created a huge problem on the InterWeb, caused by a design flaw. Instead of sending shortened URIs in SMSs only (counting the actual length of an URI as the maximal length of a shortened URI), they decided to alter the content on arrival. Now every URI on Twitter is short, all original links are lost in nirvana. Every URI on Twitter can vanish any moment, forever. Check your referrer stats for Twitter, their clones, and services like FriendFeed that republish massive amounts of tweets. Do you want to lose this traffic, just because some stupid URI shortening service went belly up?

Probably not. But reality sucks. New URI shorteners --with fancy stats and sometimes even serving advertisements-- are launched daily, and every dog and its fleas flood social media sites with unreliable short URIs. Doh!