Wish they mentioned exactly which train had this issue...because this was probably my train. On Tuesday, all the Old Colony lines were experiencing delays of at least 20-30 minutes. My train home, 019, departs at 4:40, and is usually at the platform when I get to SS around 4:25.
On Tuesday, there were no trains on tracks 11-13, so when one showed up around 4:30, everyone assumed it would be used for 019, the next Old Colony departure, but they assigned it to 083 to Greenbush at 4:52. So, they did give us the next train when that showed up at about 5 pm, and we departed around 5:05. Now, the next Middleboro train is 021 at 5:12, and it's usually packed with people going to Quincy Center (019 has some people going there, but 021 has waaaay more for some reason), so we took on a lot of people who rightfully didn't want to wait for that train (which also ran 30 minutes late), hence all the crowding and people not getting kicked out of the vestibule like they normally would. I'm betting this door that didn't shut didn't have a handle on it, so there was no easy way to keep it closed, and a conductor would need to reset it for it to work properly.
Last night we had door issues too--one set of doors wouldn't open, and finally the conductor yelled over the intercom for people to not open doors on their own, but they did anyway because the conductor took his time getting around to opening them and people were scared that they'd miss their stop. The conductors also didn't check tickets the past two nights, but that's for another topic...