I don't know quite what defines an understanding of fashion, but I think I have a coherent, practical grasp of what it's about.
I see fashion as a herd game, which one might wish to play in order to underline belonging in a group. However, as the latest fashion items are usually rather more expensive than my clobber, I feel that there's an element of exclusion, a filter that keeps out those with less disposable income and acts as a status symbol or resource display, which is perhaps important when establishing who is the alpha if the group is a (competitive?) hierarchy. I suppose the "herd game" thing may be more of a uniform game than a fashion thing, if the clothing and accessories are relatively fixed over time.
I get the comments on art, and I think art is a good thing when it comes to clothes, but I don't really hold with the idea of a highly-paid fashion designer being the best person to design clothes for a community. I prefer ordinary folks to work out how to use a sewing machine and roll their own artistic creations. Naturally there may be some people with more of a flair for such art, but I don't think it's good to put a small number of artists (from a population of millions) on a pedestal as the top dogs......it could work better in a small group, but with a big group I think it just ends up serving big business interests.
For some folks it's just a bit of fun for a large wallet, trying on funny hats for the sheer joy of seeing what happens. I have a bit of money to waste these days, so I don't feel so negative about such things as I once did, but I could never see conventional fashion and trends as being particularly important to me or my lifestyle - just a bauble really, but I see no need to destroy it.