[Johnny555]

I don't understand why transit agencies seem to reinvent the wheel when it comes to signalling, Caltrain spent $250M+ on a custom CBOSS PTC signalling system.... which I think they recently abandoned in favor of a standard signaling system.

[bobthepanda]

The precursor agencies and corporations in New York developed signalling systems that were cutting edge in the '30s, since there weren't a lot of multinational signalling suppliers back then, nor were there a lot of metro systems.

The current situation is what happens when you don't fund a replacement for several decades.