Over here in Germany, they ran against a brick wall:

• Taxi apps already existed. Pioneers were taxi.eu, where a consortium of local dispatchers plain and simply introduced another way to access their services, and what’s now called Free Now, circumventing the old dispatchers, directly connecting clients and individual, licensed, taxi drivers. Both predate uber’s founding, and definitely uber’s introduction into the market here.
• Regulations exist. Taxis are classed as public transport, prices are regulated, no congestion pricing, no not taking on a passenger to the outskirts because you wouldn’t get a return fare, no nothing. On the flipside you need a license so that there’s few enough taxis around for every driver to still be able to make a living. Uber didn’t care a bit about that kind of stuff, bringing us to
• Regulations are enforced. Drivers taking uber fares without both taxi and passenger transport license were looking at court orders giving slaps on the wrist, but also threatening 1000 Euro fines for every subsequent passenger transported without proper licensing.

Oh:

• Public transport is a thing. Most trips are covered by buses, metros, etc, more rural areas by collect taxis. Needing to hail an individual one is very rare, I think most of their fares are from people with too much money on hand. Also if you need to hail that taxi chances are your health insurance is going to cover the cost they prefer you hauling your broken leg to the doctor with a taxi, transport ambulances are more expensive and it’s not like you need medical supervision on the trip, or the thing would need to accommodate a wheelchair or such.