A couple of years ago I built a website for a client of mine. The build went without any major problems and the time came for the site to launch.
Upon launch I give my customers a crash course in how to use their CMS (in this case WordPress) so that they can update the content. My client came in to see me and brought along their friend who was an “expert in using websites.”
Expert: What size font is that?
Me: It’s 14px.
Expert: Are you sure?
I open up Chrome dev tools and show them the CSS stating 14px.
Expert: We’ll have to agree to disagree.