"According to the SFMTA, prior to 1909 there was no formal planning for San
Francisco's street names. Duplicates were rampant, and the US Postal Service estimated that they mishandled around 500 letters per day. Mayor Edward Taylor eventually put together a commission to remove duplicate street names and correct those that were misspelled. At the time there were four Church Streets and three sets of numbered streets—one set in the Sunset, one in the Mission, and one in Bayview. Street names would also change block by block, despite being continuous (Castro and Divisadero, anyone?)."
[
hoodline.com]