Problems that seem rampant throughout Wikipedia:

- misformatted disambiguation pages (see [[WP:MOSDAB]], and repeat after me:
  "Wikipedia is not a dictionary")

- article titles or section headings that are over-capitalized --
  see [[WP:MOSCAPS]], and learn what a proper noun is

- Including "is a phrase that refers to" in the lead sentence of an article.
  This is usually superfluous, and it's incorrect unless the title is italicized
  (see [[use-mention distinction]] and [[WP:BETTER#Use of 'refers to']])