From The Huffington Post
In the seminal book “The Four Steps to the Epiphany”, Steve Blank introduces the concept of “customer development” – get out of the building and interview customers. While this is not a new concept – product people with user-centered design training have always done this – this is a huge development in startup-land, where technology used to run amuck.
Challenges with sample size
There is one small problem with customer development. It relies on qualitative research techniques like detailed interviews and observation, which are time consuming and costly. Additionally, these techniques involve deep interactions with a few individuals, and you always run the risk of talking to the wrong people about the wrong problems.
How do you know whether you can trust your results? One way is to increase sample size – but given each interaction can take a couple of hours all-in, trying to get to 100 conversations quickly becomes daunting.