Similar experience. I built a very small online helpdesk platform in the early 00s. This was to support my own business mostly. I had several paying customers after 6 months. They were HELL, particularly when it came to paying the bill. I sold the whole business for pocket money after a year to a small tech company who rewrote it into a fairly well known commercial product. I couldn't be bothered. I have ZERO regrets about this.
I still have the source code somewhere, which was about 25,000 lines of ASP in one file!
I’ve done enough freelancing and side jobs to know that I didn’t enjoy and—most importantly—didn’t care enough to get better at the customer service aspect of it.
I still have the source code somewhere, which was about 25,000 lines of ASP in one file!