Whether it’s political decisions, product introductions, or military calculations, there are some ideas that looked good on paper, but failed miserably in execution. So while the Argentinean decision to invade the Falkland Islands or the introduction of Crystal Pepsi (great idea until you tasted it) looked great on paper, they were unmitigated flops because the decision makers made costly decision making errors on faulty assumptions. In its operation as a plan sponsor, employers can make decisions on their retirement plan that look like great ideas, but will be potential disasters if executed. This article should serve as a guide for plan sponsors to dissuade them from making decisions that may come back to haunt them.