I didn't mean 'everything'. Things that do require specialized knowledge are already used by a very specific subset of people. Its about common everyday things

I didn't mean 'everything'. Things that do require specialized knowledge are already used by a very specific subset of people. Its about common everyday things. We have a washing machine which I totally can't use without going through the manual, reading which number and which light does what. You shouldn't need to carefully go through a manual to just wash your clothes. There is another book "User Interface Design for Programmers" by Joel Spolsky from which my take away was that no one is going to read all your manuals and documents. Both of these essentially boil down to making things obvious for your end users.