Definitions change under the influence of time.
The beauty industry may have been the first to dilute the pure definition of this word by applying it to a chemical treatment of the hair that, in actuality, is very temporary. Subtle morphing of absolute definitions into less-defined contexts is occurring within the digital sign and printing industry as well. As long as everyone agrees on the definition, no harm. I think overall, sign-makers are reacting with appropriate wariness about what durable is. Scrimger acknowledges that a transition is occurring and that a new mindset is needed to meet it.