I bought a corner chisel (as well as other chisels) made by Barr. The bevels on the corner chisel are skwed at about 85 degrees. Where the two bevels meet in the corner they come to a point such that when in use the chisel will first cut the corner and then thes sides as the chisel is tapped with a mallet.

It is not obvious to me. Why is the chisel made this way?

Thanks in advance,

Joel