Online services have a very small window of opportunity and if you don't listen to your consumer - today, things can tern pretty fast.Late for whom? WhatsApp seems to have a massive user base.
Remember BBM? if not, allow me sketch their story. Not yet 5 years ago, hundreds of millions addicted bbm'ers couldn't imagine their world without bbm. Goverments all over the world where planning to build BBM houses of rehab. But the problem solved itself. Blackberry didn't listen to their consumer base, and crashed, head first, into the septic tank.
Whatsapp was the best alternative and, going going going, and bam, sold for 20 billion to the guy with the white shirt at the back.
Today Telegram is growing very fast in Asia. There is a huge adoption through company endorsement, making it the platform of choice also for domestic usage. Cross platform, multi-client, cloud syncing, easy API, all stuff that Whatsapp doesn't offer.
As said, things can go quick. As a Facebook shareholder I wouldn't be too amused to find out that 10% of the market cap has been spent without a clear future.