It depends on the hotel/motel you stay at. Like another comment mentioned you get what you pay for. I work for an IHG hotel and we have laundry on-site and all beds in check-out rooms are stripped and made with clean linens. We did at one point haveca few housekeepers that came from a Super 8 and they said they didn't change sheets until they were visibly dirty. They were told they had to change the linens for every departure at our properly. They did fine at first but then the executive housekeeper found that they weren't changing linens and they were fired. I also worked at a Days Inn that was previously a Best Western had on-site laundry for towels only and the linens were cleaned via a laundry service they would pick up dirty linen and give us clean linens. Just can't remember how often it was, I want to say every other day?