1. You're the CIO of your company. Like every year, you're allocated a certain budget. You figure out a way to save the company beaucoup bucks this year through some clever technology/ implementation/ etc. But you know if you don't spend your entire budget this year, come budget time next year there's no way your going to be allocated the same amount. You'll get much less and have to fight over every dime of that. Who wants that? And the company might need a bigger IT budget in upcoming years. So what do you do? Of course you spend the full amount and ignore the savings.
2. You're the director of marketing of your company. You have a certain amount to spend on advertising, both offline and online. You know that the offline stuff just isn't working anymore. Audiences are shrinking and, accordingly, impression prices are increasing. Online's not much better, but online audiences are growing, and prices are more reasonable. Problem is online actually can be measured for effectiveness, offline can not. So what do you do? Of course, keep pouring money into the offline stuff. Your company has a history of spending money there and since there's no measurability your budget can't be slashed (and you can't be fired for bad ad buys).
3. You're the VP of engineering for a start-up. From your years of experience, you know that the most effective team for the product you're building is a small one. Hiring lots of people takes time, is a distraction and won't lead to a better product. However, your CEO and your board are pressuring you to grow the company faster. In their mind that means getting more people on board and quickly. Essentially, you don't hire more, a new VP of eng will. So what do you do? You get the recruiter on the phone, the product be damned.
Anyway, I'm sure there are countless situations like these that people run into every day. These are three that I came up with. I just find it fascinating when history plus the cost of change trump individuals making the right decisions.