We can be kind enough by pressing "OPEN DOOR" button in elevator

 When you are in the elevator,

it's so important for you to....

press the "Open Door" button as long as possible...

because there are few groups of people who need kind people to hold the door longer such as...

1. A person who is carrying a child

2. A person who is pushing a pram

3. There are too many people who are waiting to enter the elevator

It's as easy as pie to do good, in the elevator.