Suppose you want to clean a large, dirty wall as quickly and thoroughly as you can. You could use a toothbrush, but it would take you forever. So probably you'd opt to use the biggest brush with the most bristles you can find. Now scale the problem down. If you want to clean a worktop really well, what's the best thing to use? You can't use a gigantic brush or even a huge cloth, but you can achieve the same effect by using a cloth that packs more punch into the same cleaning area. An ordinary cleaning cloth has fibers made of cotton or a synthetic material such as nylon. You've seen pieces of cotton so you know exactly how big the fibers are. But a microfiber cloth has far more fibers and they're much smaller. If "many hands make light work", so do many fingers—or many micro-fibers.