Two of these (plus another, Price Parrot, that I forgot to include: https://sandpiperhq.com/pricing !), are spin-outs of a side-project (https://quailhq.com) that I started in 2014and that I've been working on for 7 years -- and that became my full-time job in 2021. That one definitely isn't a failure!

The five (six including Price Parrot) are just the failures from this year. I try to live by "fail fast"!