Walkable climb to make small steep slope walkable

I’m using a Recast Graph, and I want slopes under a certain to be walkable no matter how steep. Please see example below. I set Max Slope to 60 and Walkable Climb to 10 (much larger than the height of the ground slope). Notice however, that there are holes in the terrain mesh on the slope, even though the height from the top of it to be the bottom is less than Walkable Climb. Does Walkable Climb not apply to sloped objects? Does it only work on shapes with 90 degrees that mimic stairs (e.g. see the white cube on the ground, where mesh actually was generated so that units could go to the top of the cube).