Depends on how you’re preparing them. If you’re doing a hot Italian-style pasta dish, you want to lift the al dente noodles right out of the boiling water and into simmering sauce. The starchy water clinging to the noodles will make the sauce silkier and the hot noodles will drink in some of the sauce as they finish cooking in it. Likewise, for most stir-fries, you want the noodles drained well but not rinsed. Throwing hot cooked noodles into the mix will help the seasonings, meat and vegetables cling to the tangle.
Noodles destined for room temperature or cold dishes benefit from a rinse. When noodles cool down, they can clump and taste pasty; rinsing them keeps them loose and arrests the cooking process so they don’t go limp.
The first time my grandmother ever tried to make noodles, she put a pot of water on the stove and walked away without knowing she had to turn on the fire.
