I cringe when I see founders act as though they’ve “made it” after getting their first customers or securing a round of funding. While acknowledging that you’ve gotten your company off the ground is certainly worth celebrating, maintaining a successful startup requires unwavering focus and determination.

After working in six different startups and advising hundreds more through Harvard Innovation Labs, I’ve found that founders who follow these tips are the most successful in the long run:

Be open to parting with equity
As your company grows, you need to keep bringing in the right people, from investors to advisors and employees. Do whatever it takes to get these people, including parting with equity for the resources that improve your startup’s chances of success.

I’ve seen a lot of founders go down the wrong path because they are too focused on retaining all of the equity. They obsess over the eventual payday from an exit, and decide after they bring on their initial management team and investors that they won’t dilute their ownership any more than they already have.

I believe it’s much better to own less of something successful than all of something that fails.

Maintain the right balance between confidence and humility
Even if your startup has experienced some success, you’ll still be faced with rejection left and right. People will tell you that your startup won’t be able to scale, or will surely be squashed by a bigger player in the space.

See also: What Jessica Seinfeld Says Every Entrepreneur Should Know About Success

While you must have confidence in your business to constantly face doubters, make sure to maintain your humility and not let your ego get in the way. Never stop listening to feedback from trusted sources, and be willing to admit when you’re wrong or need to change some aspect of your business. Some of the best ventures end up with a very different idea than the original.

Learn from new competitors
As your startup grows, chances are opportunists will take note and start entering your industry with similar offerings. The most successful entrepreneurs welcome new competition, and strive to continuously offer better products and services than any other company in the market.

As an entrepreneur, I’m always concerned if I don’t see competitors entering the space my startup is in. More often than not, it means that they know something about the industry that I don’t know.

Don’t be afraid to fail
Having experienced some success, you might be tempted to play it safe. After all, if customers seem to like the first iteration of your product or service, why bother changing things up too much?

I see fear of failure as one of the greatest barriers to long-term startup success. If you want to keep selling something that is truly better than anything else out there, you’ll need to take risks in making your offering better, faster, or cheaper. If there’s a significant shift in customer sentiment, you might even need to pivot to an entirely different product or service line. Be relentlessly focused on providing something of value, and constantly listening to customers’ needs.