One of the biggest benefits of testing comes from writing the test prior to the implementation (TDD). In a statically typed language, your test won&#x27;t compile until the implementation is there, meaning this process is less accessible to you.<p>Type systems focus on making sure you <i>write the code correctly.</i> They help not at all whether you&#x27;re <i>writing the correct code.</i> In the end, this is on you, the developer, to express correctness in the type system. So the theory goes if you can define the problem correctly in, say, Haskel&#x27;s type system, (up front, mind you), you may not even need any tests. But most systems are built with incomplete information. You can&#x27;t know everything ahead of time. Often what is ultimately &quot;correct&quot; is to ship sooner rather than later, learning what is systemically correct as you go along. This is where dynamic languages do well.