It often depends on the amount of detergent you use or the hardness of the water. Try adding a little more detergent or changing the water temperature.
It depends on the model of the dishwasher and how dirty the dishes are. Usually one capful is enough, but check the instructions on the bottle for more precise instructions.
Mainly in the scent, but sometimes in the ingredients. Some people prefer certain scents or are sensitive to certain ingredients.
Sometimes it can be due to insufficient rinsing or not enough detergent. Check that you are using the correct amount and rinsing well.
Yes, many people do it for kitchen surfaces, but be careful with delicate materials. Always test on a small area first.