who is doing the ranking? based on what?
i can tell you i've been in cities where the dangers in going out at night were far far worse than lagos, including joburg and douala and kingston.
when i was younger i learned which parts of new york were dangerous at night, though i'd mostly feel free to walk in 90% of the city.
the time i spent in lagos, with its universities, its cultural centers, its art, its parks, was extremely enjoyable,. traveling with conor ryan helped too; visiting kelani helped; lagos was a rich site, with transportation issues like most superbig cities,
but a life and culture that was pretty vibrant.
to rank it low must mean these things didn't count for the reviewer, so i am skeptical.