3) Minimum Viable UX test as prototype

A key early goal for a start-up should be the creation of a concrete example of your “idea”. How are you actually going to solve the problem you have identified and make it a reality? You then need to get this example in front of real people (not friends!) and measure their response. This could be as rudimental as some pencil drawings (although I do like using tools such as Pop or marvelapp)

Without this key stage, there is often a lot of hot air and handwaving when the founders try to explain “how it’s going to work”. I think this goal has two outcomes… 1) it forces you to focus on the practicalities of your solution 2) it’s the first chance for real feedback about whether your idea adds any value. Previous to this, any feedback you received on your idea will have been made on their assumptions and imagination!
Don’t expect to get the first prototype “right”, but you should hope to see people confirming that you are solving a problem for them. If not, you may want to reconsider your idea!

It is key that you use this artefact to iterate your idea – it is much cheaper, quicker and efficient to change now! This minimum is also probably the first chance for you to get real feedback as to whether your core loop is right/valuable.