When filing for a patent or copyright, say “I believe this is worth $1m” — so you pay a $20k tax on filing/renewing it. If you’re not confident that your idea can actually redeem 2% of that stated value, then maybe it’s too risky to actually be worth that much. So you say it’s worth $100k because you can definitely make at least $2k from it.
But if you’re really only confident in making $2k from your idea, and someone else is allowed to “buy license to use your material” at $100k, you’d be absolutely floored to make so much money from that idea. So if you end up being wildly successful, you’ve still made a lot of money (and can keep using your idea), but now competition/reuse is allowed past your stated value threshold.