I did a little rock raking today. What's up with that?

Remember the dirt? Of course you do or you haven't been paying attention. There were lots of rocks in the dirt so I have been raking up the rocks. Why? So the mower won't throw them through the window.

I am about 60-70% done with the rock raking. So far I have raked up 5 wheel barrow loads of rocks. These are all smaller than my fist, most are smaller than a golf ball. I had previously spent some time picking up the larger ones. Today as I was working in the hot sun, I asked myself why are you doing this? I did not have a satisfactory answer so I called it a day.