It actually started as a bitcoin company that ended up pivoting away from btc in 2014 because our potential customers didn't seem to care about bitcoin or even knew what it was even though they were accepting it via bitpay at the time.

At the highest level we were helping merchants sell more goods by building better relationships with their customers. We were able to align our revenue with our customers so we earned more the more we helped them grow theirs.

I'm not sure if it's the most surprising but one thing I learned was that it's okay to enter a market that has competitors (and is often a good sign if others are doing it) as long as you have a way to differentiate yourself. Initially we followed (i think, paul graham's?) advice to do things that don't scale. We provided manual customization and other 'enterprise'-like services to smaller customers and made sure they were happy with us as a way to bootstrap early revenue.

Eventually we were able to split the business into one that offered both a self-service and more enterprise services.