I found this hilarious article today and thought it worth mentioning.
After a while, some of the senior developers got a little suspicious of this rosy picture and went in after-hours to look at the tester’s scripts. To their amazement, each and every one of them consisted of a single line “Return True” (or the actual code equivalent). This tester had tested nothing, but instead just reported everything was perfect.
When we were writing JUnit tests for our stock management software development project last year, there was definitely the temptation to just write assert(true); on the simple stuff. I mean, you KNOW it works, you just ran the program and everything looks fine. Still, we dutifully wrote our unit tests for our little methods and learned something in the process.