Why are public transports in Switzerland so much more developed than in neighboring countries?

It's almost impossible to live without a car in Germany or France (except perhaps in big cities like Berlin/Paris, or if you spend your entire life in the same city), but in Switzerland it's clearly feasible, unless you live in a really remote rural area. However, most of the territory is still much more accessible by public transport, you can take a PostAuto/CarPostale bus to a remote mountain area. And SBB/CFF is much more reliable than Deutsche Bahn, or even SNCF or TrenItalia.

What makes it this way? Even in countries with a similar size to Switzerland, like Belgium, public transport doesn't seem as developed. And it probably costs just as much to have such a developed public network, right? Is it a byproduct of Switzerland being rich, which allows it to maintain good public transports?