Then once the equipment is decided, the playing field changes. Football players know the field is 100 yards long, basketball players know the basket is 10 feet high, baseball players know it's 90 feet between the bases, and the baselines and service lines are universal in tennis. Yes, golfers do face a different course each week, but the game plan is basically the same-drive it in the fairway, get it on the green, make the putt. The racer's playing field is different from week to week. They must determine if its better to run the bottom lane or the higher groove, and not only will it change during the race, it might be different the next time they return to the speedway.
Weather conditions affect all sports, but they affect racing in a different fashion.
Sun and clouds affect the air temperature, which affects the track temperature, which affects the tires, which affect the car's handling, which affects its performance. I hear people who aren't race fans say the sport is boring, just a bunch of guys in fast cars riding around in circles. They don't have to like it, but they shouldn't dismiss it without understanding the races within a race. I know I'm guilty of disliking things that I don't understand. Some of the best competition on a Sunday afternoon happens back in the pack and not up front all the time.