What extra stock a later bend or mill still needs on the blank
A flat blank is not the finished size. Add bend or mill stock before nesting. The kerf already gone does not pay for the next pass.
After the cut
What the toolpath offset does, and what a later bend, mill, or joint still needs on the blank.
What kerf compensation changes on the toolpath
Kerf compensation offsets the toolpath so the slot sits in the waste. The drawing stays unchanged. Check the first part with a caliper.
How a Press-Fit or a Joint Clearance Differs from Kerf Compensation
Kerf compensation offsets the toolpath to hold drawing size. Joint clearance is a second number for how tight a tab and hole sit after the cut.