Back in the '70's, I was invited to take over an apple orchard with 120+
trees that have never been pruned. That first year I picked three pick-up
truck loads of apples - they were all smallish and I spent a good part of
three weeks to do the picking.
During the following Spring I pruned. After I finished, the orchard's
owner looked at the carnage exclaiming, "You've killed my trees!" That next
Fall, I, again, picked three loads of apples and it took barely over one day
to accomplish the entire harvest. The apples were huge.