Unfortunately, aside from high performance vehicles or optional performance packages, original equipment tires don't tend to be that great. The priority of the vehicle manufacturer when a customer takes a test drive in a new car is that the ride is quiet and smooth so the customer will purchase that new car. Long tread life, handling, performance during inclement weather, etc., are really of no concern to the vehicle manufacturer and a tire that does well in those categories will also be a more expensive tire, diving up the price of the car the vehicle manufacturers are trying to sell, which is a big no-no for them of course.
This is why substantial improvements in handling, braking, inclement weather performance, tread life, etc., can be made with installing better tires than the original equipment tire.