Here's why:
* Collective nouns represent a group of individuals or things. "Collection" refers to a group of items gathered together.
* They are singular in form but represent a plurality. You might say "The collection is on display," even though it's comprised of many individual items.
Examples:
* "The collection of stamps is quite valuable." (Group of stamps)
* "She has a beautiful collection of antique dolls." (Group of dolls)
Let me know if you'd like more examples or have any other questions about collective nouns!