»Can't take the N train?

In San Francisco, some MUNI stops have absolutely no indication of where to board to catch which train in which direction.
I was getting off the inbound J at Church and Duboce, and heard a grandmotherly woman with a young kid in tow ask the driver where to catch the N; he said, "There, across the street." A moment later, the J had turned away and the woman was standing on the corner, confused.
Platforms on either side of the street beckoned; one read "N, J lines outbound"; at the far end of another, a ragged sign read "Proof-of-Purchase line." But no clear signs, no direction indicators, nothing.