I always like using the analogy that the body is just like a car engine. Anybody familiar with cars understands that you’ve got to allow an engine to be broken in. If the engine has some miles on it then you need to allow it time to warm up after you fire it to ensure you can have an enjoyable trouble free ride.
Fluids have to warm up, hoses have to warm, and the oil itself needs to warm so it can become a bit less viscous and less like maple syrup. All of these factors play into the engine running better lubricated, smoother, faster, and without setbacks. Your body works in the exact same way.