What surprising things have you learned from talking to customers?

I make a habit of talking to my customers/target market regularly, but it was only recently that I conducted my first proper customer discovery interviews.

Here's an example of something I learned which was a real surprise to me.

One of our key features is that we authorise payment when a customer books, but we do not charge them until the work is complete.

We assumed that everyone knew this (we thought it was clearly communicated), but watching various people using the site, it became clear that no-one realised this.

In fact, I was surprised myself that it didn't actually state this anywhere during the booking process as we genuinely thought it did.

An easy fix, and hopefully one which will increase conversions (the users during the test indicated the payment upfront issue may be a turn-off for them).

Has anyone else had any similar revelations arising from talking to customers?