Don't FAIL me now
Shortly after it became so popular, your mom was sending mass emails with links to a particularly funny photo, the word "fail," usually written in all upper case, became the choice word of bloggers who prefer to utter their opinions in snarkier tones. Then it went on to enter the lexicon of sassy teenagers. When my then-15-year-old brother visited me last summer, I swear I heard him say "FAIL" twenty times a day, both out loud when we encountered an unwieldy motorist while driving as well as under his breath whenever my being twice his age was made clear as I played parent for a total of 5 minutes at a time.
Recently, I've encountered the use of the word in the Catholic blogosphere and Twitterverse. But, unlike on the regular Internets, it's used not to point out situations of obvious failure, rather to point out things those who've co-opted its use disagree with. And this often comes across as mean-spirited and less than charitable.
For example, can charity and love be discerned in tweets that link to the work of another Catholic writer with the word FAIL next to it? Is it kind and compassionate to say in the title of a comment on a Catholic website (or any kind of website) that the blog post you're commenting on is a failure, even if you have very good reason to disagree? Or is it fair and just to title your blog post "Why XYZ FAILS" and then link to XYZ?
Using the term FAIL improperly makes you sound mean and bitter. Also like a teenager.
What makes the term FAIL work as a humor device (that's not mean-spirited): The thing that you're saying is a failure has to be obvious. Disagreement does not count.