Okay, batwings too, for the same reason as the phd's. Your statement is true, but look at the automotive world. I guess it could be argued either way if it is built-in failure or coming to the conclusion that enough owners aren't greasing their u-joints, ball joints, or tierod ends that they can save a few pennies by not making grease provisions without increasing their failure rate.
Let me qualify my statement a bit more. I was coming from a CUT background and point of view. When you start talking about batwing mowers you are looking at more of an industrial/commercial type situation where regular maintenance is far more likely.
Brian