Recently I was asked this question; “Why is 11 point font the default on docs and pages if 12 point font is the most popular sized font used?”
It may be statistically accurate that many different text fonts are frequently set as 12 points on 14 points leading.
The practice of graphic design and selecting type size is not a popularity contest. Font and point size choice are part of a bigger whole, these choices are partly a reflection of target audience need.
Many factors impact a visual communication device and a human beings ability to read a page in a book, or column of text in a magazine, or text content of a website displayed on a phone, tablet or desktop computer monitor. The process of reading is important. Good typography supports reading and it forms the words that communicate information, thoughts, important ideas from one mind to others. Ideas and idea exchange is key, it results in learning, opinions, peace, innovation, it is paramount to human beings.
Good typography is the result of informed, carefully made and considered decisions, it is a part of the practice of graphic design. A graphic designers choice of typeface, type size, line length, word-spacing, letterspacing, tracking, kerning, leading or line spacing all these combine and contribute to quality typographic composition. The reading process is enhanced because good typography results in how effectively the words communicate.
The dynamic balance between legibility and readability is what makes for good typography, this is part of what setting type is about. The reader should not be aware of the typography, good typeset text is almost invisible. When the typography is transparent to the reader you have readability. In a long publication, a book, magazine article, annual report, or instruction-manual readability becomes extremely important.
Many typefaces with text weight fonts perform well and have readability and legibility when set at 11 or 12 point size with 13–14 point leading using line lengths or paragraph width from 10 points to 30 points. So your going to encounter and employ these type specifications in variations and combinations when working with body copy text in many visual communication applications and media. For a very broad target audience demographic using these type specifications happen to be a practical, common problem solution.
Quality typography composition is very hard to do. Despite what the proponents of DIY and marketing people of Microsoft spew to convince one to think that using MS Word is typesetting and the inexperienced and untrained can achieve good typography and quality communication using it. MS Word is a word processing program, it isn’t typesetting and the content generated has to be remade to use it to make acceptable typography and design layout art for commercial publishing.
You have to start somewhere and for the inexperienced, defaults in word processing or dedicated graphic arts programs start the journey.
You can change defaults using properties or preference settings, if you want the default to be 12 point on 14 point leading, then change it.
These are my observations, opinions and an answer to why is 11 point font the default.