I've worked with a lot of smart executives in my long consulting career (and a lot of not-so-smart ones [I won't give any names here], and a very few really stupid ones). When it comes to making hard decisions, many make the mistake of taking careful deliberation and spending as much time as possible sleeping on them and making sure every piece of data is being included and considered. The problem is our conscious mind has limited processing capability (unless you have a quad-core hardwired in your brain). So no matter how long and careful you think the result will still be crude and ineffective. Many of us do not realize this. How many of us can calculate different competitive moves by a competitor or different responses from consumer for a particular design? How many can calculate all the risks involved in a new venture to launch a revolutionary interface for a traditional product? That is beyond our human hardware capability and the more we do it, the more diminishing return our thinking effort will be, in the end we make slow and ineffective decisions.
So what is a better way to do it? Don't kill yourself when making these decisions. Use your unconscious mind rather than your conscious mind as it has far more processing power. Use your conscious mind to collect all data and analyze them, but don't go over and do it. Instead go to perform some other activity (jogging, playing piano, meditate or simply go and sit in a Starbucks for 2 hours watching people) while your unconscious mind absorb the data in a fuzzy manner. A day or two later, the conclusion will be the best choice.
Quite a bit of scientific study out there revealed that the longer people spend thinking about a decision, the more likely they will include irrelevant information and then the quality of their decisions actually drops. Although sometimes you cannot verbalize the logic of the decision process, the gut feel or intuition has proven to help people making higher quality decisions. If you've ever worked with people like Steve Jobs you will understand why he relies so much on his intuition. Many who work with him couldn't understand why sometimes he can make quick decisions without pouring through a sea of both useful and useless data.
Many people think strategists like us only base our recommendations purely on data. While it is true that we are often fact-based when we look at a problem, but when it come to solving them, the best recommendations come from our intuition and our creative mind. Maybe I shouldn't have told you this. It was supposed to be a trade secret.