Yea I figured this may be mentioned, it's the same in the UK they were running very old train stock of the same vintage until (I think) this year? I know it's also not the only problem but both the Japanese and UK cartridges aren't complete shit and falling apart.

Three times in the past 2 years (since I moved to the G line) the train had to be evacuated because the brakes locked on a car and someone smelled the awful burning it thinking it was an actual fire in the car. THREE TIMES.

If you maintain the cartridges there's no problem at all but there are so many problems it's way beyond that.

I'm a little of a train nerd (if not obvious) so I went to the train stock as an example but other underground systems prove that proper, well funded and well managed maintenance will make this a non-issue.

"Proper. Well Funded. Well Managed." - Not the MTA Subway System