Open Door Buttons On London Underground Trains?

A double question:
Can someone explain why there are a) open door buttons on many London Underground trains (like the Jubilee Line) which have absolutely no purpose, and b), why people insist on pressing them, despite the fact the doors open automatically?

What Time Is Usually London Underground Sistem Open?

Further to Lazer’s comment. At present the whole Underground system is being renovated, after decades of neglect, so you may find some stations or networks closed at weekends; for example, the “Charing Cross” section of the Northern Line tends to be closed most weekends. The great thing about the Tube (and London’s transport network generally) is that you will invariably be able to find another route to get you to your destination, without too much trouble.
It’s always sensible to check the Transport for London website before travelling at the weekend. And remember that the short-term inconvenience will give us all a better travel experience in the long-term (thanks Mayor Ken).

Is The Bt Post Office Tower In London Open To The Public?

No, its not.
It used to be, and there was even a fancy revolving restaurant as well, but when the IRA tried to plant a bomb at the top around 1976, it was permanenetly closed to the public as a security measure.

Will Harods Be Open At Christmas?

(in london) and what are the working hours?