With a mouse you have to locate the object on the screen and then click on it, this is not efficient and may slow down work speed. But if you use a keyboard you will only have to press a button and then the same task is done, this is more efficient and it will save time in work especially if you use applications such as Microsoft word or excel.
The main advantage is that your hands never have to leave the keys. Using a mouse, you have to grab the mouse, position it, click it, return your hand to the keyboard and find your home position.
