While I prefer scouting out a location; but that does not always work out. If I get to a place right before sunset, I will shoot right away because by the time I scout the area, the light may no longer work. The same thing goes if there is an event that will be over quickly, I will take my chances and shoot, but will move around to work the scene if time permits.
In a perfect situation, I will scout things out and then come back to shoot later. Taking your beach example. I was out and saw this scene, which was nice enough, but I knew I wanted to come back closer to sunset.
When I did, I got this. The bonus was I got the lighting I was hoping for and the fog rolling in which I did not expect.