Linux, the open source operating system that virtually powers all of webservers, billions of Android phones as it’s kernel just as well as the majority of home routers and IoT devices, turns 25 years this year. IEEE Spectrum runs an article on the history and why the open kernel became so successful.
Also, Linus Torvalds has an approach that would be called agile these days. Bringing a feature in place is more important than having the 100% solution, and Linus explains this approach in the accompanying Q&A session:
I’d rather make a decision that turns out to be wrong later than waffle about possible alternatives for too long.