diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index b60a9d39..006063e3 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -29,6 +29,7 @@ This is the most simple project when it comes to contributions, setup, opening i
 - When adding a Unit Test
 - Take care of the file name convention
 - Make sure CI (Travis) is passing
+ - Expanding the test suite until (close to) 100 percent code coverage is achieved
 
 ### Notes
 
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