I remember putting one on over a plain black cami and jeans before a work thing I nearly cancelled, and standing in front of the mirror thinking it looked like I'd made an effort without actually making one. That's the whole appeal for me now. It does the flattering bit on its own, the tie sits where your waist actually is rather than where a size label thinks it should, and you haven't had to think about it.
Where it falls apart is when you pile too much else on top of the idea. A wrap top with a wrap dress, or with a skirt that's got its own big waist feature, just looks like you're trying to make two statements at once and neither lands. I've also learned not to wear a very fussy necklace with mine, the v neck is already doing a job, and a chunky necklace fighting for the same space ends up looking cluttered rather than finished. Plain jeans, a straight skirt, or simple wide leg trousers let it do its thing without competition. And go easy on bold patterns underneath if you're wearing it slightly open, a loud bra or cami showing through the gap is not the look.
How it wears depends entirely on the fabric, and I've had both ends of that. A cheap jersey one I bought years ago went baggy round the tie within a few washes and never sat right again. A better quality one I've had for two summers now still holds its shape, because the fabric has a bit of weight and some actual stretch recovery rather than just stretch. I wash mine inside out on a cool cycle and never tumble dry it, heat is what kills the wrap shape fastest, it loosens the fibres right where you need them tightest. Hand washing is better if you've got the patience, I mostly don't, but I do always lay it flat rather than hang it, because wet jersey on a hanger stretches at the shoulders and never quite recovers.
Seasonally I reach for mine most in spring and early autumn, under a blazer when it's a bit sharp out, or on its own in a heatwave because the wrap front means it's never clingy even on a sticky day. It's good for anything where you want to look like you dressed properly without actually being dressed up, a lunch, a casual work day, a dinner where you're not sure how smart everyone else is going. Size down if you're between sizes, because the wrap is built to be adjusted and a too big one just means more fabric bunching at the tie.