Don't rinse your pasta unless you're making a cold dish.

No. Rinsing spaghetti after draining is almost always a mistake.

The starch on the surface of cooked pasta is what helps sauce cling to it. If you rinse, you wash that starch away, and your sauce slides right off. You’ll end up with a plate of sad, slippery pasta swimming in a pool of separated sauce. Rinsing also cools the pasta down, which is the opposite of what you want for a hot dish.

There are only two exceptions. One: you’re making a cold pasta salad and need to stop the cooking immediately and cool it off. Two: you’re using the pasta in a stir-fry or fried noodle situation where you want it completely un-sticky and cool before hitting the wok. That’s it. If you’re just tossing it with marinara, aglio e olio, or cacio e pepe, do not rinse.

If you’re worried about sticking, toss the drained pasta with a little olive oil instead. That works fine and doesn’t wreck your sauce situation.

Save the rinse for salads, not sauces.