From the comments about pivots, there are arguably two forms:
1) after digging a deep hole, or even a mine, deciding no treasure, and starting a new mine
2) checking whether the shovel breaks the surface easily, and moving around till it can dig
It may be true VC want diggers to see how deep the mine can go before giving up, it may also be true VC want diggers to scrabble around surface area at the start until there's at least some sign of purchase. Those aren't exclusive.
1) after digging a deep hole, or even a mine, deciding no treasure, and starting a new mine
2) checking whether the shovel breaks the surface easily, and moving around till it can dig
It may be true VC want diggers to see how deep the mine can go before giving up, it may also be true VC want diggers to scrabble around surface area at the start until there's at least some sign of purchase. Those aren't exclusive.