I only recently started thinking about style and fashion, so I can still remember those confusing early days.
When you're first starting out, it's nice to have just one monicker and just one set of guidelines so you can figure out just one thing at a time (ie, figure flattery). Trying to figure out personal style and figure flattery and adapting trends to your climate/lifestyle/preferences, ... well, I remember feeling completely overwhelmed. I think once you're a bit further along (as evidenced by the number of "veterans" responding on this thread), you can start talking about "figure flattery priorities".
At this point, I'm comfortable with being an "inverted triangle", a "cone", or even a "V" ... but if you asked me 2 years ago, I would have been flipping out in confusion over the difference, mostly due to different guidelines between different "experts". I remember being particularly confused about one site saying "v-necks look good on ITs" while another one said "wide v-necks look terrible on ITs". Nowadays, I realize it's about wide necklines drawing attention to my shoulder width, but back then I needed specific and actionable suggestions.
I think a site like this is valuable in that it demonstrates how clothes can help you appear more like the idealized hourglass. Someday, I'd like to see someone discuss why hourglasses are the ideal, though!