One of the most common mistakes that teams made was treating specifications or related automation code as less important than production code. Examples of this are giving the automation tasks to less-capable developers and testers and not maintaining the automation layer with the same kind of effort applied to production code.
Reference: “Specification by Example – How successful teams deliver the right software”, Gojko Adzic, Manning, 249 pages, IBSN 978-1617290084