Why do founders have a hard time telling their stories simply, elegantly... powerfully?
Founders know A LOT. Domain expertise, market intelligence, IP defensibility, product roadmap, customer pain points, and on and on. They are really excited to share ALL THEY KNOW and all the hard things they have accomplished and overcome.
But... There's something called the Curse of Knowledge. Chip and Dan Heath's book, Made to Stick, makes the point that "You don't know what it's like to not know what you know." Read that last sentence again. You and your Co-founders have been reading the same emails and Slack channels. You may even be eating all the same take-out. You can finish one another's sentences. You are in synch.
However, that can lead you into a false premise that others -- outsiders, barbarians at the gate -- can also easily understand what you've been up to. Investors won't make the leaps of logic you are making because they aren't in your head. They haven't been reading your Slack channel for 14 months.
And that's a problem. Because chances are the investors are used to understanding things quickly. When they don't get your new, new thing in a few minutes, they are not likely to say, "It's not you, it's me." They'll just move along.
As 9X founder Scott Brown says in his book (C)lean Messaging, "As soon as you are telling somebody about your company, it's no longer about you." It's about finding a universally accessible message that is easy to grasp right from the jump.