On 28/04/2017 19:03, Mr Pounder Esquire wrote:
DerbyBorn wrote:
Why do we scrub the heavy thing back and forth when it has fast
revolving brushes? Surely a single slow pass is just as effective.

Same as using a hover lawn mower and moving from side to side when just
forward does the same job.

People like doing things even if pointless. Like flapping Polaroid
photos while they develop.

--
Max Demian