Why doesn't Paul's mother have any luck in Rocking Horse Winner? What does luck mean to her? When Paul asks his mother if she isn't lucky, she...

Paul's mother says she is "very unlucky" because she "married an unlucky husband".  This indicates that she does not take responsiblity upon herself, but instead blames others for her lack of happiness.  When Paul asks her if she was lucky "by herself", she responds that she "used to think (she) was, before (she) married", but when Paul looks at her closely he perceives that "she (is) only trying to hide something from him".  Paul's mother is unlucky because her values are skewed.  She is so consumed by desire for material things that she is unable to see what is really important in life.  She has a son, at least, who loves her beyond measure, but she herself can "not feel love, no, not for anybody".

Paul's mother thinks that luck is "what causes you to have money".  She says that it is "better to be born lucky than rich", because "if you're rich, you may lose your money...but if you're lucky, you will always get more money".  It is ironic when Paul is confused about the term "filthy lucker".  He has heard his Uncle use the term "filthy lucre", and since "lucker" and "lucre" are pronounced similarly, and his mother associates "luck" so closely with money, he thinks the two terms are the same.  Although his mother points out that they are not, in reality they kind of are.  Using his mother's interpretation, both refer to money and its power to corrupt and destroy.