A little more than a year ago, Secret CEO David Byttow was getting ready for his appearance at a top industry event and eager to talk about his anonymous sharing Secret app going public in February 2014.

What a difference a year can make.

On Wednesday, April 29, Byttow took to another social site, Medium, and announced he and the Secret board of directors had decided to shutter Secret and will be returning what was left of that initial funding back to investors.

"This has been the hardest decision of my life and one that saddens me deeply," wrote Byttow in the Medium post. "Unfortunately, Secret does not represent the vision I had when starting the company, so I believe it's the right decision for myself, our investors and our team."

He then praised the Secret team, noting the product was in use by over 15 million consumers and had "pushed the boundaries of traditional social media."

The closure comes as the marketplace for social and sharing apps has become a crowded, competitive space. The decision proves that providing online users Internet anonymity remains a big challenge, given all the negative aspects and activities that can be produced.

One media report noted how Byttow stated just last month that he had no plans to close down his startup.

In his announcement this week, the CEO offered insight into the implications of using anonymity in online communications as a selling point.

"I believe in honest, open communication and creative expression, and anonymity is a great device to achieve it," wrote Byttow. "But it's also the ultimate double-edged sword, which must be wielded with great respect and care. I look forward to seeing what others in this space do over time."

For the next few weeks, the CEO plans to shutter Secret in a graceful fashion, vowing to eliminate and destroy all user data. The company still had a "significant" amount of capital on hand, and the correct thing to do, he said, would be to return the funds rather than "attempt to pivot."

"Innovation requires failure, and I believe in failing fast in order to go on and make only new and different mistakes," added Byttow, who also vows to share his insight, lessons learned, challenges and mistakes he and his team had from the 16 months that Secret was up and running.