Chesterton's Fence is the principle that reforms must not be made until the reasoning behind the existing state of affairs is understood.
An essayist named Chesterton (wikipedia) was discussing reform and how to go about it. He used an example of a fence that was erected across a road. An 'innovator' might come across the fence and say, "This makes no sense. I can make a positive impact on the world by removing this fence". Chesterton argued that he would let this innovator do no such thing until this person had figured out why this fence was put up in the first place. In doing so, he would have understood what use the fence had and only in light of that knowledge be allowed to destroy it.
As tech lets us innovate and disrupt things around us at a faster pace than ever, we have become blind to the failings of our "progress". This is not an argument for status quo or against creative destruction. When we understand the benefits of old systems and processes, our innovation can account for these much better.
India's recent 'de-monetization' policy is a great example of this. Certain denominations of currency notes were made illegal overnight in a push towards digital payments. The goal was to increase accounting and taxability of the economy. The outcome has been terrible (though there's plenty of spin in the media). Most of the harm fell upon the impoverished -- for example, the under-banked who could not take time away from their jobs to change their "de-monenetized" cash in time and lost their lives' savings (NPR's coverage). The economy seems to be going into a tailspin as well (a former Finance Minister writes about this). Asking why the fence was laid in the middle of the road might have been a good idea.
Plenty of startups make this mistake too, and don't fully understand the net effect of their product or service on early customers. But the destructive power of startups is usually limited to themselves.
A deep understanding of the why's behind the current state of the world is very likely causally linked to a favorable outcome for your startup.