Using both hands and assigning specific fingers to certain values helps improve both speed and accuracy in abacus calculations. If a single finger is used for all bead movements, calculations take longer because more steps are required. For example, adding a number like 9 may require multiple bead movements if done with one finger. By using the correct fingers, these movements can be performed simultaneously in a fraction of a second—making calculations much faster. This method is similar to typing: using the right fingers for the right keys increases speed and efficiency. Additionally, using both hands helps stimulate both sides of the brain—left and right hemispheres—enhancing coordination, concentration, and overall cognitive development.