By natural instinct, most people and organizations tend to get defensive and protect their ideas and products when they start to go beyond their control.
I'm not talking about Blockbuster who refused to move forward when it was clear that their model of movie rental were about to go bust, and Netflix did it right by leaving it behind to pursue streaming.
It's more like the very first LEGO Mindstorm programmable robots. They were hacked in record time, and instead of getting defensive about it, LEGO left it to take its natural course and used it as an enabler to win the enthusiasm of the casual DIY hackers who wanted to have fun programming a robot. They let it go out of their control.
They even embraced the hacks and you can now connect your code to a LEGO Mindstorm robot from almost any platform or programming language. The community blossomed, and is a huge advantage for them, which they'd not only miss out on but also spent a lot of energy to fight, had they chosen to prevent people from hacking their Mindstorm brick.
Another example is WattPad, their simple take on writing stories has become huge community of writers and readers that together create new indie-authors and book titles that becomes sucessful.
If you allow your initial idea to be a little open and un-controllable, it can help your users guide you in what you need to focus on next.
In the early days of Facebook, there was no way to upload photos.
It was simply an “online directory that connects people through social networks at colleges”. Meaning the core functionality was profiles, the ability to connect to friends, and then browse the profiles of your friends and other people in your college. One key feature of the Facebook Profile was the Profile Picture. Which, users were passionate about. So passionate, in fact, that users were changing their profile picture multiple times per day. – Get Out Of The Way
When you add elements of self expression and free form input abilities to a product, people themselves can get creative and do what they want, which is a way of telling the creator what they might need to focus on next.