Men are very visual creatures.
I know many, many women who have let themselves go over time because they get comfortable. Wearing sweatpants all the time, letting the gray hair grow, no makeup, not shaving, old clothes, becoming prudes, and the list goes on and on. Some women simply stop trying. I will never understand this.
While I may not agree that this ends marriages, it could lead men to have wandering eyes.
I agree with this.
I work from home so the majority of the time I am that woman in sweats with no make-up. My husband has never complained or said a word and our marriage is good but I have no doubt that he loves to see me dressed up and with make-up. I feel the same way about him. It's nice to see each other looking our best.
So while I don't think a lack of effort should end a marriage, it certainly can't hurt one to make an effort.