When I was a 26-year old MBA student at Northwestern, I took a class called "Creativity and Personal Mastery" that required us to keep a daily journal for two months. After graduation I continued writing in the journal, a Word document that eventually exceeded 800 pages. 

When I turned 30 I stopped journaling and entered an exciting decade full of highlights like getting married, having two sons, and starting my company, GMM Nonstick Coatings.

In my 40s, I hit my stride, balancing my roles as husband and father with growing GMM into one of the largest companies in our industry and investing in tech startups. In my late 40s, I sold GMM in a landmark buyout and stepped away last year after turning 50. 

As I thought back on my career recently, my mind drifted back to the journal. The file had languished in my cloud drive for decades. I decided to upload the sprawling, disorganized document into ChatGPT and ask it to find blind spots in my youthful worldview.

I wasn't expecting much. But in under six seconds it spit out an alarmingly accurate analysis.

My first reaction was astonishment at the capabilities of AI. My second reaction was: "My wife is going to have a field day with this one." Which she did. 

The AI summary of my youthful shortcomings was embarrassingly precise, capturing traits that, while diminished, are still part of who I am today. 

The experiment allowed me to reflect on the hunger and ambition I had and the challenges I faced in my 20s. But it also helped me see what I've learned along the way and understand why I'm happier now than I was then. 

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I'm happier when I rein in my perfectionism

The perfectionism ChatGPT picked up on made the first few years of starting my business miserable. I got frustrated when things didn't work out exactly as I wanted, which was pretty much every day. So many things were going wrong. 

Over time, I learned to reframe my expectations and understand that the difficulty and messiness is baked into the game. This revelation makes it so much easier to keep going in tough situations.

Some of my downfalls contributed greatly to my success

When I showed this analysis to 10 of my friends in YPO — a business network I'm part of — every person looked at the list, nodded silently and tallied how many of these traits they shared. "Eight." "Seven." "Nine." "All of them." 

These were all founders of large businesses, people with great spouses and kids, who I generally regarded as being pretty good at life. Tendencies like "overemphasis on external validation," or "high expectations of self and others" can link to, or promote, drive, persistence, and execution. But they can come with steep costs to well-being. 

The key is having the self-knowledge to not go too far and, in time, most of us have learned to find the right balance.

Winning at all costs can be a net loss

When I was young I relished "winning" arguments. I loved backing up my positions with facts, nodding while the other person talked and only half-listening as I crafted my next clever point. 

But as I matured, I realized that needing to always win is a recipe for loss. I ruined a few relationships years ago because I didn't know when to shut up. 

Today I'm confident in my judgment, but I am mindful to not be judgmental. I know the point isn't to "win" but to listen, learn, and connect. That's what people will remember. 

I work hard at enjoying the moment

I've always struggled to just relax and enjoy the present. But I've gotten better at it by making a conscious effort to appreciate each moment and never take things for granted.

A few years ago, I gave a commencement speech at my high school. I talked about how the most successful moments of my career (closing a deal, selling a company) always seemed anticlimactic.  

The point I tried to emphasize to the students is that "the value of achievement is in the achieving." The journey is the gift you must learn to enjoy.

I value close relationships most of all

Last year I got a tattoo with the phrase "memento mori," Latin for "remember you must die." 

Remembering our time on Earth is limited makes it impossible to not value close relationships with family and friends, by far the most important thing we all have. I make sure our kids spend lots of time with my parents, and see how close I am to my sister and her kids. 

We also go on adventures together. In the last two years, we took a trip to see the pyramids in Egypt, hiked through the Andes to see Machu Picchu, and visited India to see family and the Taj Mahal. Later this year we're going on a safari in Africa. 

Knowing that I'm not wasting time fills me with overwhelming gratitude. 

I want to pass on these lessons, but my kids might have to learn for themselves

I've shared some of my reflections with my kids in the last few weeks. Part of me wishes I could help them skip over some of the obstacles and hardships I faced, to get more quickly and easily to the peace of mind I've found. 

But a mentor once told me that "the biggest advantages we cannot give our children are the disadvantages we grew up with." 

As they grow up, my kids will have to walk their own paths. They'll discover their own blind spots, learn their own lessons, and find their own success and happiness.

Ravin Gandhi is the founder and former CEO of GMM Nonstick Coatings and a member of the CNBC-YPO Chief Executive Network. As a VC investor, Gandhi has stakes in KeyMe, Hester Biosciences, Ka-Pop Snacks, SenSanna, Apptronik, Amber Agriculture, Ampsy, Throne Labs, Tred, and Lettrs.

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