Why are SV06 Z motor mounts not square (90 degrees)?

Before I dive into ABS printing to make new Z motor mounts for my SV06 I was hoping someone could tell me why the OEM mounts aren’t 90 degrees square. When mounted to the gantry they definitely slope down toward the front of the printer.
I’ve checked with a couple of squares and the angle is greater than 90 degrees. I just don’t know why this would be. It doesn’t make sense to me.
The biggest thing I don’t understand is why the mounts would be made this way. They are injection molded parts. That takes time and costs quite a bit up front. It’s hard to imagine how a part that costs so much to create would not be checked to ensure it meets the specs exactly.
Can anyone help me understand?