The reason it works is because humans, at least non-visually-impaired humans, have no trouble reading these distorted squiggly characters, whereas computer programs simply can't do it as well yet.
Ona djeluje zato što ljudi, barem oni koji nemaju oštećen vid, nemaju problema s čitanjem tih iskrivljenih vijugavih znakova, dok to kompjutorski programi jednostavno još ne mogu tako dobro.