Question - Why is it recommended to use a key attribute for directive?
Answer -
It is recommended to use a key attribute for a directive to track each node's identity and thus reuse and reorder existing elements. We have to provide a unique key attribute for each item with in v-for iteration. An ideal value for the key would be the unique id of each item.
Example:
That's why it is always recommended to provide a key with v-for whenever possible unless the iterated DOM content is simple.