Hmm well, when you send Bitcoin, you're actually using the receivers pubkey to chain that bitcoin to a locking script.

So kid gloves, Everytime you send Bitcoin you're writing a note to that person that says they have x number of bitcoin. Each note is a utxo. You can have 1 note that says you have 100 sats or you can have 100 notes that each say you have 1 sat. In each case you have 100 sats, but in one case you have 1 utxo and in the other case you have 100 utxos.