Question: Why do we need to worry about change? Shouldn’t it be enough to send the exact amounts plus fees?
I'll paint a scenario in which people have lost very large amounts of Bitcoins.
This is how NOT to do it:
1. Import your paper wallet into a wallet
2. Send a small transaction
3. Delete the wallet assuming the remaining balance is still on your paper wallet
4. Realize you've lost thousands of Bitcoins and will never be a crypto millionaire
It depends on the wallet how change is treated, but it's safe to assume change will go to a different address and not back to your own paper wallet,
unless you take precautions!
That's why it's better to sweep the funds into a wallet (make sure you create a backup of the wallet
before funding it!), make payments from there, and send remaining funds back to a (new!) paper wallet if needed.
Further reading:
Five Ways to Lose Money with Bitcoin Change Addresses