Usability guru Jakob Nielsen:
Overall, people with strong technology skills make up a 5–8% sliver of their country’s population, whatever rich country they may be coming from. Go back to the OECD’s definition of the level-3 skills, quoted above. Consider defining your goals based on implicit criteria. Or overcoming unexpected outcomes and impasses while using the computer. Or evaluating the relevance and reliability of information in order to discard distractors. Do these sound like something you are capable of? Of course they do.
What’s important is to remember that 95% of the population in the United States (93% in Northern Europe; 92% in rich Asia) cannot do these things.
…
You are not the user, unless you’re designing for an elite audience.