“Bookend the Future” is the title of the tenth chapter in the book Decisive by the Heath brothers.
This is the writer's explanation of the concept:
Penstock uses a method he calls “bookending,” which involves estimating two different scenarios: a dire scenario (the lower bookend), where things go badly for a company, and a rosy scenario (the upper bookend), where the company gets a lot of breaks.
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Although I fully understand the concept, I couldn't define a meaning for the word “bookend” and put it into words so I can recall it easily.
According to the Oxford online dictionary,
Bookend: as a verb means “to be positioned at the end or on either side of (something).”
But I think that this definition doesn’t apply here.
As far as I understand it, this concept is a kind of guesstimation.
I want to know what a native speaker would understand by the phrase “bookend the future”. (I don’t want to have to recall the whole concept every time to interpret the phrase.)
Can you help me with a simple definition for the phrase “bookend the future”?