No aspiring entrepreneur has all the information they need to start a business upfront. Many lessons about startup life are learned through experience, and you can't and won't know everything in advance. However, it can help to have some insights and advice from those who have been there before.

To help prepare you for the journey of entrepreneurship, here's one fact that existing entrepreneurs believe every startup owner should know prior to launch day. Take their lessons to heart if you're planning to start your own company.

Business impacts your personal life.

Entrepreneurs can experience burnout and other adverse effects if they allow their entire life to be consumed by their business. That's why Amber Anderson, founder of Tote and Pears, recommends having a business plan and a personal plan in place before you launch.

"For the first three to five years of my business, I was all-in," says Anderson. "The lines between work and life were gray, which impacted my husband and me both mentally, emotionally and financially. By planning ahead, we created boundaries that helped us to grow our business and our relationship together."

You need a unique selling proposition.

You may think you've got a multimillion-dollar idea, but every aspiring entrepreneur should research their competitors thoroughly to define their unique selling proposition, says Mark Stallings, co-founder of Casely, Inc.

"Why would someone buy your product instead of an established brand?" Stallings asks. "A concept so unique that you don't have any competition is rare, but it happens. Just ensure you're solving a problem or meeting a need with sufficient demand."

You have to know what you can personally give.

Before your startup officially launches, you should consider how much time and skills you can personally contribute to its growth, says Stephanie Wells, co-founder and CTO of Formidable Forms.

"You can't do every single thing, so knowing what areas you'll need to hire for or partner in is crucial to running your business efficiently," Wells adds.

It's not going to be easy.

Most entrepreneurs know starting a business is going to be challenging, but you may not be prepared for exactly how difficult the journey can be.

"There will be moments where you'll just want to leave everything," says Alfredo Atanacio, co-founder of Uassist.ME. "In our society, entrepreneurship is revered, and it may even sound heroic and glamorous to have your own company. In reality, it's a lot of work, a lot of sleepless nights and a lot of important decision-making."

Things will take longer than you expect.

According to Richard Fong, CEO and founder of ABCDreamUSA.com, everything about starting and growing your business will take much longer than expected to figure out.

"Traction may seem attainable at times but remain just beyond grasp due to unforeseen challenges and setbacks," Fong explains. "Maintaining an attitude of tenacity is key."

Knowing your finances is key.

Kristin Kimberly Marquet, founder and creative director of Marquet Media, LLC, says every founder should know the different types of financial statements that exist and how each relates to their business.

"They should know how to create them, what each one means, how to read them and why these documents are important to their businesses," Marquet says.

You can't do it all alone.

There's no such thing as a truly "self-made" person, says Brian Greenberg, CEO of True Blue Life Insurance. Every entrepreneur needs a mentor who's been down the path before and can share their own struggles and stories of success.

"A mentor's past experience can help you to navigate today's business climate," Greenberg says. "You can often find mentors through sites like LinkedIn, and some communities even offer small business meetups that can help you engage with other entrepreneurs."

You might fail.

As unpleasant as it may be to imagine, there's always the chance your startup will fail. Being prepared for that possibility before you start is critical.