Whenever I tape legs I always have to cleanup one side to get the
beginning of the taper perpendicular to the leg.

I am curious why? This leg that was squared in the planer has pencil
marks for clarity.

One side is perpendicular,
The other side is not. The blade comes up all the way thru and then
some, I use a high blade not just thru.

The way I rotate offers support on the backside.

Does anyone know why this is happening? I am getting tired of fixing
these after the fact.