This article originally appeared in Inc. If you like this article,

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My time spent in business classes boils down to two lessons. One of them is about the rule of assumptions; namely, that when you take any assumption for granted, you inevitably set yourself up for potential failure.

That truth never became more real for me than a month ago, when we were selected to be the marketing agency for a company going public. The reason: We didn't assume we knew who their target investor was. When we pitched, we told them that many agencies will come in with an idea of who the target is, and that we would do no such thing because no one could know until people started to put their hard-earned dollars on the line.

That was enough to tip the scales in our favor. Not only did it remind them that the smart approach is to always test assumptions, but it also showed them that we were more humble than our competitors. In fact, humility and the rule of assumptions have been pillars of our rise from no-name startup to multimillion-dollar, international company.

It may very well be that your incorrect assumptions are why you're coming up short in business. Here's how to use the rule of assumptions to gain back that competitive advantage:

1. Simply question everything

Today's most exceptional companies (think Uber, Facebook, Amazon and more) are inquisitive by nature. They consistently ask "why?" until people turn blue in the face, and constantly test their assumptions against actual market responses. Engender a culture of curiosity by instilling the rule to never assume anything. When you do that, you will visibly see your organization becoming more ingenious, innovative and successful.

In fact, there are times when we even question what our prospects and clients are asking for. We routinely get asked to do activity X, and turn around to offer them solution Y, because we question their needs and come up with a different root assessment. Rather than anger them, we have experienced surprise and appreciation that we were thinking critically about their needs rather than just taking orders.

2. Systemize your stance on assumptions

Aside from creating a general culture of curiosity, weave a general rejection of assumptions right into your organization's processes. For instance, our method for launching IPOs is to develop hypothetical consumer personas, assess those personas with split-testing across digital networks in a wide variety of markets, and finally deliver a proven target persona, ad set and geographical market that we can then use for more robust marketing efforts. With the process written out, it's impossible for our creative teams to circumvent it as they find that invaluable data for the client.

3. Use the rule of assumptions to beat your competition

We make a big deal out of rejecting assumptions. Not only do we stress our develop-and-test iterative approach to prospects, but we also remind prospects that most agencies think they already know the answers and unload those assumptions onto their weary clients.

Unfortunately for the industry that's a true statement, and most prospects we encounter nod their heads in agreement. Luckily for you, this doesn't only happen in the marketing industry; it happens in every industry. So, if you can be the provider who takes this kind of approach, you'll immediately stand apart from your competition.

One of my favorite phrases in business and in life is, "we don't know what we don't know." I've been surprised to learn that being humble, open and vulnerable about the reality of our mostly-unknown world is a fantastic way to win millions of dollars' worth of business.

So the next time you think you know the answer, remember that when you assume, you put yourself at risk of being wrong. Instead, go in with an open mind, and the right answer will surely find you.