Greg Koch was a wannabe musician who ran a rehearsal studio in Los Angeles for renowned rock bands like Fear Factory, Fishbone, and the Melvins. Then he co-founded Stone Brewing, which quickly became enormously influential in the craft beer world, thanks to its strong brews and even stronger personality. Stone Brewing is a 12-time Inc. 5000 honoree. But forgive Koch for being more excited about a recent collaboration with Metallica. --As told to Graham Winfrey

My favorite bands were ones that just went for it. Early Jane's Addiction. Metallica. Primus. Nobody ever asked for the kind of music they were playing.

I didn't look for a niche in the market and decide there was a place for a craft beer with a strong personality. It came from my music background, and just wanting to freely express who we are. It's a DIY mentality, often associated with punk rock--a go-your-own-roadness and a rejection of the norms.

I never expected to sell more than maybe 100 cases of Arrogant Bastard Ale. In 1997, nobody in the industry would have said people wanted a 7.2 percent alcohol, overly hoppy, overly aggressive beer. It was a reflection of my feelings at the time, which haven't completely changed: a high disdain for a corporate mentality and those lowest common denominators generally exuded by large brands. The label that I wrote for Arrogant Bastard calls a lot of that out very directly. It lets people know that they should expect something different--and that it's probably not for them.

But it became the top-selling 22-ounce beer in U.S. chain stores. Stone IPA is our No. 1 selling beer, but Arrogant Bastard Ale remains a very important part of our portfolio. It helped put us on the map.

When my co-founder, Steve Wagner, and I first tried that beer, we looked at each other with one of those silent wow expressions, like, "Holy crap. This is amazing! How did we do this?" Of course, Steve knew: He had made a mistake with the recipe. He'd accidentally doubled the amount of hops and specialty malts.

To me, "cult brand" just means that you're hardcore doing it the way you believe in, and other people are responding. It means that you get known for the quality and character of what you do--not some ad campaign, or something else that falsely inflates it.

Beer Advocate named us the No. 1 All-Time Top Brewery on Planet Earth in 2008. It was pretty fucking nuts when that happened. What I love most about that is that no one person decided that. It was a combination of all of the ratings of all of their users.

In 2014, a year and a half before we hired Dominic Engels as CEO, I talked with Steve­--he's now our chief cultural architect--and our board and our executive team, and said, "I'm feeling like my experiences are a little too limited for where we are trying to take this company." We now have around 1,200 employees. Operating Stone takes a different set of skills. Mine were focused on growing the company and less on internal health, and we wanted to improve the experience of our own team.

I was always pretty certain that I wasn't interested in private equity. But VMG Partners had done tremendous research into craft beer and into Stone. I could tell they weren't faking it. They really understood craft beer, and made it clear that they cared about the things we cared about. In 2016, they invested $90 million. A minority investment, so Steve and I still maintain control. So, even if they were jerks, I suppose it could be OK. But I'm happy to say that they're the opposite.

Enter Night Pilsner happened because Metallica decided that they were interested in making a beer, and Stone kept coming up in their research. When they reached out to us, I was skeptical. Now, I'm like, "You should've known. It's Metallica. They take things seriously." They didn't want to just rubber-stamp their name on something. They wanted to be involved, and really understand the process.

We're two entities that came from the fringes. In our early days, what we did and what they did weren't popular.

To achieve popular success based on that cult foundation is, for me, kind of the holy grail. It's the thing I'm most proud of.