Although the station platform only allows room for a three-car trainset, when the station was first opened a six-car trainset was used on the line. In this case, only the first three train cars' doors opened at this station (selective door operation). It was not until 22 July 2006 that a dedicated three-car trainset began service on the line. https://en.wikipedia.org/wiki/Xiaobitan_metro_station
https://en.wikipedia.org/wiki/Selective_door_operation
https://en.wikipedia.org/wiki/Taipei_Metro#Platforms
https://en.wikipedia.org/wiki/Multiple_unit
