In business, success is associated with “Yes.” Yes to a new deal, Yes to a new market, Yes to a crucial new hire. Many businesses will reflexively say “Yes” to any and all opportunities, no matter how difficult, daunting or outside their core competency it may be. Yes is also the quickest way to destroy a brand.

That’s because branding is a long-term effort that requires a singular direction, a highly defined niche and constant diligence. What makes a brand strong is consistency; brands are powerful because they set a certain level of expectations and meet it over and over again.

That’s why truly strong brands understand success starts with the word “No.” In the B2B world, long sales cycles make it tempting to take on clients or initiatives that are a poor fit for both your company and the customer. While the best-case scenario might be a foothold into a new market, the risks are endless: poor reviews, a ruined reputation and a sullied brand image, not to mention wasted resources on a business you shouldn’t have gotten into in the first place instead of investing in what you know.

From Crystal Pepsi to McPizza, history is filled with unfortunate Yeses. And as much as this feels like it should be yet another reason to shake your head at the ’90s, this is a mistake brands keep making. Here are just a few off-brand fails from the last few years:

Zippo The Woman PerfumeEva Longoria’s Steakhouse for WomenPaula Deen Kids’ FurnitureDr Pepper MarinadeAriZona Tea Nachos ’n’ Cheese Dip

For each of those core brands there are certainly logical brand extensions to make. Fans would perhaps buy Paula Deen cookware, Eva Longoria lipstick, or try an AriZona Tea kombucha. But what does a lighter company have to do with perfume, a glamorous actress have to do with steak, a famous chef have to do with furniture, or drink brands have to do with marinades or prepackaged nachos? We have no idea, and we suspect fans of the core brands don’t either.

In the case of each of these brands, they could have spent the same time, money and effort strengthening their core brand instead of chasing a shiny off-brand opportunity. We get it; no one wants to turn down business. But by creating products that are a poor fit, taking on clients outside your expertise or going into markets where you don’t have a compelling story, you can end up busying yourself with unprofitable work while leaving yourself unavailable to pursue and service your true customers.

How do you know when to say “No”? It all comes back to your brand. Believe in what your brand stands for and stick to it. If it feels off-brand, take caution. By making your brand a part of your decision-making process, you’ll have a powerful tool for making the decisions needed to grow your business. Including when to decide “No.”