Abstract

The poor mechanical stability of microtextured surfaces is a major barrier to their engineering applications [1,2]. Accordingly, researchers have devoted themselves to developing microtextured surfaces with robust mechanical stability. Recently, Wu et al. [3] reported a superhydrophobic coating with a robust hierarchical structure and compared its mechanical stability to that of the other robust surfaces. The authors claimed that the test conditions used to evaluate the mechanical properties were the most rigorous as compared to those used in previously reported tests. As there is no universal standard to quantify the mechanical stability of a surface, the following questions are worth discussing: “how was the comparison carried out?” and “what test conditions qualify as rigorous?”