Why does the concentration gradient affect the rate of diffusion?

I know that the higher the conc. gradient, the higher the rate of diffusion, but why?Why does the concentration gradient affect the rate of diffusion?
because the rate at which a variable quantity , such as temperature or pressure changes in value The curve that represents that rate undulates.Why does the concentration gradient affect the rate of diffusion?
a high conc is like a high pressure zone..take a balloon for example..suppose u fill it up with air..the pressure inside it increases.as soon as you loosen your fingers at it opening the air gushes out, because air pressure outside the balloon is lower than that whats inside..so in case of balloon the pressure gradient governs the air movement..





similarly, in fluids, its the conc gradient.





the conc gradient is corollary to pressure gradient