Taxis are complementary to the higher-priority parts of the hierarchy. It's easier to commit to walking/cycling/public transport knowing that you can always tak

Taxis are complementary to the higher-priority parts of the hierarchy. It's easier to commit to walking/cycling/public transport knowing that you can always take a taxi in a pinch. SOVs have the inverse effect - it's hard to combine them with other modes of transportation, and if you're already paying to own/maintain/insure a vehicle, you're incentivized away from considering alternatives.