Holding doors

It seems not a working day goes by when I'm held up on the Victoria line because of the issue of holding doors:

We're just waiting for the train in front to leave the platform as they are having problems with the doors.

Can you check that you have nothing caught in the doors? We can't leave the platform until the doors are no longer obstructed.

It's simple. This is how you hold doors:

Don't do this:

Thanks.