A great post came up on a discussion forum recently. A vendor offered unconfirmed shipping as a cheaper option, but balked (in a good way) when a customer wanted reimbursement for a shipment they didn't receive. The vendor felt responsible even though the shipping choice very clearly stated "no refunds for this option." Should the vendor replace the merchandise?
This thread reminds me of that wonderful old David Bromberg song "A Man Should Never Gamble (More Than He Can Stand to Lose)..."
It's a common trap we all make, trying to offer as many ways as possible to entice a customer and make a sale. We offer high and low price points, lots of color choices, custom orders at no extra cost and lots of shipping options.
But if you discover along the way there are options that are not acceptable to YOU, then it's time to change your policies. In this case, you may find NOT KNOWING if the package was received or not, is not really acceptable to you. You may find you don't really want to say, "Hey you made your choice, now live with it." The benefit to your customer (cheaper shipping) cannot not offset the drawback to you (not making this right for your customer, but with proof they were really wronged). So a new shipping policy--offering only shipping that can be confirmed--is in order here.
What's cool about this is there is no right or wrong, good way or bad way to set up shipping policies, return policies, etc. Only what you feel is best for your customers AND best for YOU. The whole thing is a process. (I call these situations "life learning experiences" because that sounds so much more bearable than "major screw-ups.")
That's one reason I share my mistakes, in public, in front of God and everyone. In the long run, that's how you help other people sort this stuff out for themselves before it happens to them. We can't learn everything from other people's mistakes, but when we can, it's golden.
Disclaimer: No, I don't share ALL my mistakes. That would be humiliating!