Last week night I was describing two of my personal projects to a few colleagues, and I realised how inept I am at describing these things with any kind of enthusiastic conviction.
When I start to describe one of the games I'm working on my mouth is often trying to say "I'm making this cool thing!", yet my brain is thinking "...but it's not really a cool thing until you work out all these kinks". The result is I uncertainly drag out a "I'm making this... ehhh... thing. It's kind of like this and stuff, but there are all of these problems".
It's not that I don't have confidence in the concepts, it's just that there's something about being in the early/mid stages of the game design process that makes me painfully aware of how much more there is to work out, how many problems there are to solve, how many of its elements conflict with one another, how the tertiary mechanics fail to support the core mechanic, how I'm going to have to resolve that pesky ludonarrative dissonance, etc, etc. None of these things are easy to communicate over drinks after work when peoples' attention is divided.
But I guess it's OK. That design gap is is a driving force which I find myself compelled to fill. It's just sometimes a little tricky to convince others of its potential merits.