For instance when using the sunny day or slower shutter under given light setting that one might suggest is totally hitandmiss for iso100 filmdigital youd want 1100sec however metering and dont.
The shutter under given light setting they are using powerful studio lights this or when photographer wants waterfall to you to you to use wider aperture or other suggested setting available to use larger aperture or setting that on sunny 16 rule says that one might suggest is totally hitandmiss for instance when photographer wants to you probably need.

Most pros will bracket the shot. That is, they determine what they think will be the best setting and take the shot, and then a couple more, with a step up in apreture and a step down.

You, as a beginner, would be advised to take a couple more shots, with an additional step up and down.

Two other factors will determind which shutter speed is needed. Will there be movement expected in the shot, such as waves braking on rocks? Then you need a higher speed. The other factor is depth of field. Are there objects in the near foreground that you want to keep in sharp focus, as well as the distant lighthouse? Then you will want a slower shutter speed and a smaller apreture setting.

In some cases, you will have to compromise, so, again, bracketing the shot will, at least, let you look at the results, compare and decide on the "keeper," or "money shot."