URL shorterner’s life

I was perusing some emails that came from a mailing list, old blog posts that I bookmarked, and old tweets that I favorited. Many of them contains somekind of link shorterners like tinyurl, bitly, and t.co.

While the URL shorterners are still functioning just fine, the actual URL themselves are not always so and sometimes I get a 404 error message from the target website. I know link rot happens, but somehow this irked me.