Whyare the police so useless?

They seem to be here at the moat pointless crimes in history such as : riding yor bike on the path... Plahig ball in a 'no ball games' zone... But when one is being raped/mugged/murdered/robbed/kidnaped ... where are they? They are far more dealing with petty crimes with teens than the actual major crimes... :l why are they so useless..