"The greatest danger for most if us is not that our aim is too high and we miss it, but that it is too low and we reach it" (attributed to Michelangelo - disputed)
The only way to possibly achieve our best is to have crazy dreams and aim way past our possibilities.
Some years ago I had the opportunity to go and hear Edward de Bono, author of Lateral Thinking, speaking in London. He played a game with the audience called something like 'ideas from the ridiculous'. In this game he asked the audience for a problem that needed to be solved and it was suggested that there are not enough taxis in London. It is so hard to train taxi drivers: it takes years of experience to gain 'the knowledge' and so there aren't enough taxis overall. Through a very short discussion it then became apparent that black taxis would have drivers in it who knew the destination and they would be more expensive. People who had no idea of how to get where they wanted to go would hail a black cab and pay not only for the cab but also for the information.
People who knew exactly where they wanted to go would hail a white cab with an inflatable question mark on top and they would tell the driver where to go. Thus the driver in the white cab would get paid less money but would learn where the destinations were and the experienced drivers would have black cabs.
This solution was pure genius and came from ridiculous thoughts of inflatable question marks above taxis. This is the equivalent to crazy dreams.
When you're on holiday and you start writing your lists about the crazy things you would like, those are the things you should focus on and have some time to think about, not just heading straight back to work and putting your nose on the same grindstone you have always put it on but think about the crazy places it would be possible to go.
As Leonardo da Vinci said "Time stays long enough for anyone who will use it"