What's the primary departmental goal of quotas? To make it look like you're being useful?
It's a failed policy by some departments of using the amount of arrests to compare the increase/decrease in crime. It's a policy of blaming the beat cop for crime. Supposedly More arrests and stops = less crime. Crime goes up = it's because the police are not doing enough. The problem is some departments making invisible quotas for their officers that are not realistic and result in decreased morale, strained relationships with the community, and removal of police discretion to meet numbers.
So let's say you get X legit arrests per month but crime upticks, the brass start asking for more cause crime is up. Officer now is told that arrests are down and crime is up, so X is no longer enough. Officer gets X arrests as usual but now has to meet Y criteria or gets look down upon as a lazy cop by the brass. So now the citizen gets arrested for petty crimes, which is legal, but petty.
And just so people know, it's not about tickets it's about arrests and stops. Tickets are usually the job of meter maids and parking enforcement not police. This policy has been spreading to many departments as CompStat or other names. Number driven policing to map and deter crime.