If your coffee tastes too sour or too bitter, this is usually due to the wrong grind setting.
The various coffee preparation methods differ greatly in the contact time of the water with the coffee powder. In the case of espresso, the ground coffee only comes into contact with water for about 25 to 30 seconds, whereas in the case of filter coffee, the coffee powder is flushed with water for several minutes. The aim is always to optimally extract the aromatic substances of the coffee bean with water and thus to produce a coffee beverage with a balanced taste.
For those who want to know exactly: Ideally, 18 to 22% of the aroma substances should be extracted from the coffee. This creates a balanced relationship between aroma and strength.