CSS shorthands reset all the properties you’ve declared before. For example, when trying to center an element horizontally, you might use
margin: 0 auto;, which actually is interpreted as:
margin-top: 0; margin-right: auto; margin-bottom: 0; margin-left: auto;
In large projects you may accidentally override one of these properties, so you should better set only the properties that are necessary:
margin-right: auto; margin-left: auto;
The same applies to properties like
It’s not like a rule of thumb, I even dare say that CSS shorthands are good, but try not to overuse them in relatively large projects.