An entrepreneur’s journey can be full of ups and downs.  But by looking to the wisdom of others, you can get closer to what works and avoid what doesn’t.

Five entrepreneurs -- everyone from the founder of a security-software company to a removal service -- have opened up about their experience and provided insight into their journey by answering a few questions.  I asked these entrepreneurs if they were to start their entrepreneurial path over tomorrow, what you do the same and what would do differently.

Below are their answers:

Looking Back: 5 Entrepreneurs Divulge What They'd Change and Keep the Same

1. Chris Klaus 
Company: Founder of Internet Security Systems, a security-software company acquired by IBM for $1.3 billion, and Kaneva, a 3-D virtual-world business.

What he is glad he did: "Find a big problem that you are passionate about solving. When growing up, I was into playing video games and always wanted to build my own 3-D video game world.  From that early quest, my startup, Kaneva, is on mission to allow anyone to create their own 3-D world. By allowing kids to create their own world, it opens the door to programming and user-experience design, with a long-term goal of getting more kids to pursue computer science and human-computer design degrees. Before doing another startup, I would think about what big problems exist that I would like solved that could have a big impact on others." 

What he wishes he could change: "Do not pick too many goals and metrics for the company to focus on. Try to come up with a business model that has an overall simple goal and metric to measure the success by. For many early-stage startups, customer retention is one the most important metrics that is often overlooked.   It’s common to see the customer acquisition and viral metrics get a lot of attention.   The challenge is if you drive potential customers to your startup website or app, and they don’t convert into a loyal customer and return within a day, week or month, it’s not building long-term value."

Related: Funding Your Business on Your Own? Learn From These 7 Entrepreneurs

Looking Back: 5 Entrepreneurs Divulge What They'd Change and Keep the Same

2. Sarah Shupp
Company: CEO and Founder of UniversityParent, a website focused on providing information to parents of college-bound students.

What she is glad she did: "Build and grow the product by listening to our customers. While our platform to reach parents continues to evolve, we've always maintained laser focus on the problem we're trying to solve. I will always use this to build future companies. The way you're solving the problem might change, but the problem shouldn't change."

What she wishes she could change: "I would hire my team much more intentionally and carefully. Early on, I made several hiring mistakes because I felt pressure to fill a seat rather than finding the right fit. This strategy almost never worked. It may have saved me time upfront, but it cost me tons of time, energy and money in the long run."

Looking Back: 5 Entrepreneurs Divulge What They'd Change and Keep the Same

3. Michael Simmons 
Company: Co-founder of Empact, an organization focused on helping young founders succeed.

What he is glad he did: “If I had to start over again, I would continue to focus on building deep and authentic relationships. Long term, there isn’t anything more important personally or professionally than the people you’re surrounded by.”

What he wishes he could change: "I have been prone to jump into opportunities that I’m excited about without regard to my current commitments or whether or not there is a really strong market fit. I wouldn’t do that again.”

Looking Back: 5 Entrepreneurs Divulge What They'd Change and Keep the Same

4. John Ruhlin 
Company: CEO and founder of Ruhlin Group, a corporate gift-giving consulting firm.

What he is glad he did: "I would definitely choose again to have a business partner and be unreasonably generous with appreciating and gifting those I come in contact with.”

What he wishes he could change:  "I would NOT wait so long to start building my platform to speak and share my message."

Related: For Entrepreneurs, The Gift-Giving Season is Year Round

Looking Back: 5 Entrepreneurs Divulge What They'd Change and Keep the Same

5. Tyler Garrison 
Company: Founder of removal service Junk Recyclers Inc. and retail store The Regeneration Station

What he is glad he did: “I would still bootstrap and self fund. This decision is one of the main reasons we are still doubling our growth every year. This mindset simultaneously eliminates much waste while boosting creativity and sales.”

What he wishes he could change: “We could probably do what we’ve done twice as fast so long as we still maintained our conservative and focused mindset.”

Related: 5 Mistakes I've Made So You Don't Have To