Most dishwashers are designed to have a little detergent in the first cycle and then most in the second cycle. The detergent from the first cycle becomes available to the water immediately, the detergent for the second cycle is the part that you put in the compartment.
If you want to know the details, watch the rest of the video. Or, if you don't want to do that, read your dish washer's manual. Maybe yours was designed without to forego detergent in the first cycle, because people have switched to pods anyway. Maybe it wasn't, and you can get a hygiene boost by using powder instead of pods.
If you use detergent pods, one of your cycles won't run with anything but water. If you put the detergent in the tub, the longer, second cycle runs without detergent. If you put the pod in the little compartment, the first cycle is much less effective than it can be.
Many machines are still designed for powder or gel detergents that you put into both compartments. You can get the same dishwasher performance by using two dishwasher tablets per run (one in the tub and one in the compartment) but that'll use up way more detergent than you actually need.
Rinse aid is for maintaining your dishwasher, that's something different entirely.