Well, the 'best laid plans' quote has a deep significance. It tells us that life is unpredictable. The story associated with it is that Burns was out in the fields. He noticed a mouse that had made a cozy nest for the winter. The mouse had done everything right in its own little world. But then Burns' plow came along. All the mouse's preparations were for naught. It's a metaphor for our own lives. We can plan every detail of our career, our relationships, but then something unforeseen pops up, like a job loss or a family emergency, and our perfect plans fall apart.
The 'best laid plans' refers to the idea that even the most meticulously thought - out schemes can fail. In the context of the quote's origin, it shows how the mouse had built its nest so carefully, yet it was disrupted by the actions of a human. This is like in our lives, we might have great plans for a project or our future, but factors outside of our control, like illness, natural disasters, or sudden changes in circumstances, can derail them.