The last war
Of all the many valuable things Joe Kraus shared with us, the one that stuck with me the most is this: "we're always fighting the last war". I think the salient point is that this wasn't advice, it wasn't exhortation, it wasn't a problem that he felt his greater experience had given him any greater ability to solve. Intead, "fighting the last war" is something that Joe obviously reminds himself of when making decisions today, and in that sense it's an insight direct into the mentality of a working entrepreneur.
This is why I'd like to get currently engaged entrepreneurs to form the bulk of 106 Miles' speakers list. It's always fun to hear about famous success stories of the past; but it's so much more immediate to think along with someone who is going through some of the same challenges as you.