At R29, trends are our bread and butter. We debate them, write about them, and sometimes, we even fall for them. But, for every trend we're happy to see the second time around (see: crop tops, jelly shoes), there are some highly regrettable fads that we prefer - no, demand - remain conscripted to the dustbin of history. Forever.

Simply put, some trends should never have been. What mass hallucination convinced us that tiny, tinted sunglasses were cool? Why would anyone who wasn't losing their grip Avril Lavigne wear knee-high Chucks? Were mustache accessories ever funny?

Sure, we might have liked some of these the first time around - but we're undergoing hypnotherapy to forget those dark days. And if they ever make their way around the retro curve again, you best believe we're packing our (timeless, minimalist) bags and heading for the hills.

Click on to see the most hideous, heinous, and downright reprehensible trends the fashion world's ever coughed up. But be forewarned - what follows cannot be unseen.

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