When you get a pool built, there is always at least some risk of what they call a hard dig. This basically means the ground is too hard to be dug with a normal bobcat digger.
They found out within about an hour of starting ours that it was going to be a hard dig.
This meant that they had to attach a jackhammer to the end of the the bobcat and slowly try to break up the unpredictable lumps of granite they found.
This is quite a lot more expensive than a normal dig, but in fairness, it did look like an awful lot of work. Despite it being “very hard” according to one of the builders, they made what looks like good progress to me the first day:
Here’s the very noisy video: