#Housing.com to lay-off 600 employees in next 3 months
Customers dont always know exactly what they want, they will have an idea but it will be down to you to figure out the details. Prototyping helps a great deal as a way to hone in on the exact need, always get as much feedback as possible but do not listen to all of it, be selective and try to find repeating common patterns between your customers. Remember you are building for the 80% and if you get lucky you might also please some of the other 20% but sometimes that can just be a bonus.
Source : http://www.startupbootcamp.org/blog/2015/march/creating-great-financial-software-part-1.html