Streetcars are Too Rigid
Streetcars are nice. Streetcars are efficient. That's all good. The trouble with streetcars is that needs, neighborhoods, routes change over time. As the city evolves the need to move people from one place to another remains but the places change as neighborhoods spring up and decline and business moves to different areas. Since the streetcar operates on tracks it is very hard and expensive to move when it no longer takes people where they need/want to go. Buses are a whole lot less glamorous but the routes can be changed to meet changing transportation requirements without much cost. This is why over time streetcars will always lose.
