Geophysics can be a finnicky beast, You have to use your...

Geophysics can be a finnicky beast, You have to use your understanding of the structural geology to determine if the response you get is due to a small shallow conductor at a certain angle, or a large deep conductor at a different angle. There is much subjectivity and black magic involved.

In this case, it appears that the interpreted geophysics was drill tested, and found to be incorrect, the geophysical response was in fact from a larger, but deeper conductor. So it is initially disappointing that they did not intersect what they had hoped to, however this hole has helped them gather more information with which to re-interpret the geophysical response, and try again in a different hole. The fact that the conductor is larger bodes well, depending on what depth it occurs.

Short version: They missed the target, but now have a better understanding of where to throw the dart next, and the next target is bigger than initially anticipated.