Lots of stakeholders use Word, Google Docs, or some other word processor to type up the content for a web-page. Sometimes the "styles" from those word processors don't appear by default on the web. One such example is with ordered lists, switching from numbers to letters.
ol > li > ol {list-style-type: lower-alpha;}
It's way easier to maintain and update by using ordered lists (<ol></ol>) instead of trying to type the numbers/letters by hand, and now you've got a quick trick to add to your CSS snippets.