It's not wrong, but if your end goal is to attract the opposite sex, working on your outside shell should not be your main priority.
A man's confidence comes from being competent at life, not looking pretty.
Having skills like using tools and being able to fix things, being able to physically protect your loved ones and being a confident provider is a bigger turn on to women than having your hair a certain way.
That's where alot of men go wrong. They project their own attraction triggers onto women. They think cuz all they care about in women is looks, that's how women see men.
Problem is, that isn't how women see men. They are looking for signs of masculinity and competence within you, not some dude who spends more time looking in the mirror than they do.
That isn't to say you can let yourself go entirely, but it will help you understand why being "pretty" doesn't work the same way for men.
Men who spend too much time on their looks, end up appearing feminine and turning women off. Comes off narcissistic and insecure.