6. You're a grown-up, but you look like you are going to your quinceañera.
Teens rarely understand or appreciate subtlety and simplicity. That's fine. It will give them something to be mortified about when they grow up. But while it is one thing for a 15-year-old to wear a flurry of ruffles, ombré polyester, rosettes, and rhinestones, it is quite another for a grown woman. Don't get me wrong. If all that noise is really your jam, then, hey, you do you, but it is going to look cheap, even if it isn't as extreme as the example below.
Less is more, especially if you are shopping with a limited budget and can't afford high-end embellishment. And if you really care about making sure your formalwear looks its richest, do yourself a favor and just avoid ruffles altogether.