I had mentioned this in this thread before, but there is only a 1 page memory
Massa's injury was an impact injury, more than a cut. The skin would have been broken open, like a boxers. The area where he was cut, has little if any meat behind it, and no fat, especially for someone in the shape of an F1 driver.
When you get a deep cut, the flesh is used to stitch in to. As well, when someone has surgery, the cut is made with a surgical instrument, and is easier to close in a sterile environment, immediately after surgery is complete.
Injury scars, typically, do not look very good after they are fixed. There is also little that can be done, aside from therapeutic ultrasound, which helps align the cells in a scar, so it grows and heals evenly. These kinds of wounds heal from the bottom out, so for a while the scar makes the deep flesh connected to the outer flesh. This takes a long time to normalize, so you can "move the flesh" around the bone like normal).
My arm for example, when it was cut, the bicep part of the cut needed to be stitched on the 'outside'. Imagine the inside stitch of your jeans compared to the outside stitch. Massa's injury would have required the inside style of stitch, otherwise the wound would start to open like a way-too-tight button up shirt on a fat guy.
Also, when someone has a serious eye injury like Massa, they need to open up the cut area even more. When saving an eye, you are not thinking abut scars. Much like when they were trying to save my arm and keep it from being lopped off, the scarring is a secondary issue for consideration.
Here is a good example of before and after of an "outside stitch".
Hurts just posting this stuff
Before
After