Maybe Facebook just made a better offer, was simply a better fit, or maybe it was because Facebook co-founder and CEO Mark Zuckerberg once offered him a job, but either way Instagram co-founder and CEO Kevin Systrom chose Facebook over Twitter. Dorsey didn't take it too well, according to The New York Times:
Mr. Systrom may have lost one connection in the deal: Mr. Dorsey of Twitter. His company, according to several people briefed on the matter, had expressed interest in buying Instagram in recent months. Mr. Dorsey once used Instagram daily to send photos to Twitter, but he has not been back since the deal was announced, perhaps a sign that he is not happy to see it in the hands of a competitor. A Twitter spokeswoman declined to comment.
So it looks like Facebook wasn't the only social network interested in Instagram. I previously listed 10 ways Instagram is to Facebook as YouTube was to Google, noting how Facebook beat Google to Instagram just like Google beat Microsoft to YouTube. Now it looks like Facebook also beat Twitter to Instagram too. How intense.