[chadcf]

Really depends on what your app is doing and how critical it is to a business. For a complex application that has been in production for years, whose original developers weren't very talented and now are long gone, and your business relies heavily on customer satisfaction and bugs can cause lost customers and thus revenue as well as potentially exposing protected data, tests are absolutely critical.

On the other hand, a hobby project used by a few people or internally at your company where bugs can be discovered in use and aren't usually a big deal, eh.

And of course, there are a lot of levels between the two extremes...