Agreed and that’s what spiking is for! Once you have an idea of the solution then you can implement properly with TDD, which generally results in a much better design than just going with the original spike. However, I find it bizarre that many engineers think unit testing is beneath them. I can understand that people find it difficult to stick to the test first discipline. But it’s crazy to me that you wouldn’t want to write tests at all.. I feel so much happier with the additional protection.