That said, in places with good taxi service (where I*m at, for instance), there isn't a reason to switch.
(and generally high quality)
To be licensed, cabbies must master a comprehensive London geography/traffic test, the knowledge required to pass it is literally known as "The Knowledge"[0].[0] https://en.wikipedia.org/wiki/Taxicabs_of_the_United_Kingdom...
*Not as good as London taxis of course, but no place has taxis as good as London.
Until very recently, NYC's TLC required drivers to pass tests to prove geographical knowledge and basic English.
That's why people are so polarized on whether Uber and company are the messiah or the devil. It just tells you which of the two kinds of cities/areas they lived in.
I used to live in northern NJ, within commutable distance of Manhattan. Manhattan cabs, for me as a white person, were pretty easy: just stand on the corner and hail one. There wasn't any point in using Uber/Lyft because it would have taken more time to get out my phone and mess with the app! However, back at home in NJ the taxis were ridiculously bad: I had to call ahead and hope they would show up within an hour. Then they'd drive me in some weird long route to get a higher fare. Uber/Lyft were so much easier (aside from being cheaper).
Price.
Car services have existed forever. The point of Uber is making it affordable for everyone.