I started my company Chromabill (https://www.chromabill.com/) out of a necessity. College didn't teach me about financial literacy and I wanted a simple way to manage my expenses.
I loved using spreadsheets but Excel on mobile was clunky and not mobile-friendly. That motivated me to create an app to help organize my expenses, see how much my average monthly spending was, and stay on top of my bills.
Little did I know that what I had built would work for so many others! I know it's not hugely impressive but $200 MRR is still a win nevertheless!
Celebrating by reading Zero to Sold by Arvid Kahl