Jason Fried and David Heinemeir Hansson from Basecamp have a good take on low-hanging fruit in their book "It Doesn't have to be crazy at work". They say:

"Low-hanging fruit can still be out of reach. (...) the further away you are from the fruit, the lower it looks. (...) Declaring that an unfamiliar task will yield low-hanging fruit is almost an admission that you have little insight about what you're setting out to do."