Sometimes when you see a 20% off sale, you think: Eh, I'll be fine skipping this one because how much am I really saving. That is, unless we're talking about Glossier . Emily Weiss and Co. only post sales once a year, so this is your only chance to refill your Boy Brow and Lash Slick mascara for the cheap. And that's as good a reason as any to throw all your sale hesitation (and hard-earned cash) out the pale- pink penthouse showroom window.