A hummingbird's wings beat around 50 times per second (50 Hz) — fast enough to hover motionless in the air.
A housefly's wings beat even faster, well above 150-200 Hz — too fast for the human eye to resolve as individual strokes.
Contrast that with an albatross, gliding on wings that may flap barely once per second, or an elephant's unhurried gait, with a period closer to two full seconds per step.
Same physics, three orders of magnitude apart — purely a function of size.