They can play the role of the expert who gives advice as a coping mechanism to avoid looking at their own unresolved needs for power. They treat others as problems to be solved and people to be controlled. They send a message that you are not grownup enough to figure out your problem on your own and take the consequences. The tactics of a benevolent dictator creates helplessness in people who agree to play their hidden power games. This fits neatly into the Doormat's perceived need to live in perpetual atonement for past, present and future sins.
Doormats turn their own personal power over to others.
They communicate statements like, Whatever you want is okay. It's all right with me. You decide for me. They ask permission for things that other people just take for granted and go ahead and do. Say what you want straight out instead of asking permission when it is appropriate.