Difference of one setting; metering

I am posting this more for me than anything else. I want to be able to use this a reference for my own learning. Metering is crutial to getting the correct exposure. There are three types of metering: Matrix, Center-weight and Spot. At this point in my skill level, I don't plan on using Center-weight. So the difference of matrix and spot is demonstrated below. The only difference in these two shots was the meter setting.

As I understand it, Matrix metering interprets the whole scene and is great for landscape shots. It takes more of a light average.



Here I metered for the water and consequently the people are underexposed. Had I metered the people, the water would have been overexposed. Spot metering is best for face shots or when there isn't much light contrast in the picture.



Does anyone want to add in? Do I understand this metering correctly?