The relationship you're describing is contracting. Salaried employees don't have a pre-negotiated scope of work; "what's expected of you" isn't fixed in advance. This cuts both ways. If something runs late, you don't take a financial loss. But if something runs early, you don't get the time back either. The company has purchased everything you can get done in a workday. If that's more than average, it's more than average.