Why I still Lisp
&gt; What improves (and guarantees) software quality is rigorous testing. To deliver high quality software, there is no other solution.<p>This is 100% false. You can’t inject quality into a bad design via testing. You can’t guarantee quality or correctness through testing. Testing is the second worst place to find errors.<p>You get a MUCH higher roi by producing thoughtful written designs and getting them peer reviewed. And again with code reviews. (Peer review is best but self review can also be very effective.) I’m not saying don’t test — testing is valuable, especially because it forces you to design for testability, and a suite of automated tests is valuable when making changes later.