Short answer: no, not usually. Long answer: quinoa has a bitter natural coating (saponin) that needs to be rinsed in order to remove, otherwise your quinoa will taste a bit off. That being said, almost every brand of quinoa on the market pre-rinses the grain before packaging, so it's not necessary for you to rinse again at home. If you're not sure about the source (for example, if you buy quinoa in bulk), go ahead and give it a quick rinse just to be safe.