diff --git a/htest/Test/Ganeti/TestCommon.hs b/htest/Test/Ganeti/TestCommon.hs
index 22f07e8c1aeba5e3624681fff9ff3ef74452cf32..62990499fe0b0686b5240ba1e77501fcc53a1e83 100644
--- a/htest/Test/Ganeti/TestCommon.hs
+++ b/htest/Test/Ganeti/TestCommon.hs
@@ -147,7 +147,7 @@ genFQDN = do
 
 -- | Combinator that generates a 'Maybe' using a sub-combinator.
 genMaybe :: Gen a -> Gen (Maybe a)
-genMaybe subgen = oneof [ pure Nothing, liftM Just subgen ]
+genMaybe subgen = frequency [ (1, pure Nothing), (3, Just <$> subgen) ]
 
 -- | Defines a tag type.
 newtype TagChar = TagChar { tagGetChar :: Char }