Why is this so hard?

The idea is supposed to be simple. Take a block of wood, cut it to shape, insert some nails with plastic wheels on them, and send it hurtling down a ramp. Instead , I've encountered tons of advice—use lots of graphite, use only a small amount of graphite, make sure the wheels are square, leave one wheel up so you are only running on three wheels, sand the wheels down thin, don't sand the wheels down as it makes them wobble—and still I am left with only a block of wood, plastic wheels, and 4 nails. What makes it all the more challenging is that this is not your usual Pinewood Derby (Bradlee isn't in Cub Scouts yet). This is for our ward Elders Quorum Pinewood Derby night, so the competition is already fierce. I don't know what this will be on Saturday, but I fully expect to bring up the rear. Good thing this is all for fun and not any real competition!