When I worked in the Mission we watched a small homeless encampment run a bicycle chop shop wide open in broad daylight for over a month. Police regularly came by, nothing more than an old tarp was used to try hide the bicycle operation.

Increased surveillance would have made zero difference. For whatever reason the activity was simply tolerated.

Because it is a waste of time and money for the police to do anything, if the DA is going to drop the case. It is a waste of time for the DA to do anything, if the judge will drop the case. It is a waste of time for the judge to do anything, if the prisons are full, expensive and downsizing such that these kind of offenders are not exceptional enough and therefore right back on the street.