I agree with the money/time thing - I feel I look pretty good on a low budget but I do have time to shop second hand and get to work ebay etc.
It also comes down to priorities - I think some cultures/social groups it’s easy to practice good self care. Others, not so much.
You need to make your own standards.
I’ve often received negative social pressure for taking care of my looks
(from guys I date doing the whole “why are you going to yoga/swim when you could be taking care of MY social needs” .
To other women being a bit bitchy, or implying I’m desperate to get a man.
Or even my depressed mothers voice doing the whole mocking “clever girls don’t care about what they look like, you look like crap so why even bother because you’re not some uber-conventionally pretty blonde type?)
“I like shopping for clothes. I feel exercise time is an essential not a “treat”. I like being X dress size. I like looking at style blogs. I value my personal appearance. I feel more confident and enjoy socialising more when I like the way I look and feel appropriately socially dressed. Clothing is a way of creatively expressing myself. I have two (in budget) items on order from ebay right now.”
If I said the above out loud in front of some people I’ve known I’d be mocked a LOT. So I don’t, but I internally prioritise what I want to.