Uber pickup location problems: when do you cancel instead of waiting it out?

Bad pickups waste more time than a lot of riders realize. Apartment complexes with no gate code, downtown corners where you cannot stop, grocery stores with three entrances, clubs where the rider keeps saying "I am coming" from somewhere you cannot see. I do not mind waiting a fair minute when the spot makes sense. What gets old is blocking traffic, risking a ticket, or circling a lot while the a…