Learning and growth comes from trying something new, which means we haven't done it (like this) before. We haven't given this presentation, we haven't tried this technique, we haven't had this conversation, we haven't gone this far. So, it might not work. It might not turn out like we hoped. It might not create the change we seek to make. Perhaps it's because we weren't qualified, didn't have enough experience or didn't prepare enough. Perhaps the timing wasn't right, the audience was in a bad mood, the lighting failed, or the conditions changed unexpectedly. Or, perhaps we were just unlucky.
Whatever story we tell ourselves in advance of why something won't work is probably wrong. It's worth telling to sort out some real traps. But, it's just a story. No one knows for sure...until we try. Go or No Go...choose wisely.