As Richard said, the carrot is mightier than the stick. Getting your wife to change or to do something for you is much more likely if you understand what motivates her. I am not talking about manipulation here. The goal is to line up things with her values and desires so they make sense and are easy for her.
Another thing to understand about motivation is it changes over time. A change in what we value shifts our motivation. Likewise for changes in what we believe. Season of life can also affect our motivation. This seems truer for women, and especially those with children. If a woman is motivated primarily by being a mother, she may have a problem when the kids grow up. She might cling to them or become depressed. She might find some new motivation, and it may or may not be something healthy. If your wifes motivations do not seem big enough for a long full life, or if they are not going to hold up for her entire life, work to help her find additional motivation before she end up in a crisis.