The reason why center text alignment is horrible for user experience is that with each new line the user reads, there is a brief moment where the user has to find where the next line begins – decreasing the users reading speed.
In my opinion centered paragraphs are only acceptable up to a point, 3 lines of text to be specific. Anymore, it becomes too displeasing to read each line after.
Primary page titles should be okay centered as they tend to not have as many words and therefore lines of text. Most page titles aren’t long enough that text alignment becomes an issue with usability. However, with secondary titles (h2’s) and anything under should always be left-aligned to match its paragraph text.
Left text alignment should be used in 95% of cases to help your readers read at an optimal, undiminished reading speed.
You can use center alignment in small doses like main page headings without detracting from the user’s experience.
Only use justified text for mediums where its commonplace like material books or e-books.
The only commonplace acceptable use of right alignment is navigations on websites.
