Courtyard started in the US as a quality 4 star hotel primarily for business travellers. They have since moved on, especially in Asia, to be a solid quality product rivalling some 5 star properties, although lacking some of the bells and whistle extras (variety of restaurants primarily) that a JW Marriott might. Just take a look at the new breed Courtyards and you wouldn’t want to stay anywhere else, especially at the reasonable rates they offer.
PS. I don’t work for Marriott but through personal experience thoroughly recommend Courtyard especially Europe and Asia.